The following is a conversation with Nick Bostrom, a philosopher at University of Oxford
and the director of the Future of Humanity Institute.
He has worked on fascinating and important ideas in existential risk, simulation hypothesis,
human enhancement ethics, and the risks of superintelligent AI systems, including in
his book, Superintelligence.
I can see talking to Nick multiple times in this podcast, many hours each time, because
he has done some incredible work in artificial intelligence, in technology, space, science,
and really philosophy in general, but we have to start somewhere.
This conversation was recorded before the outbreak of the coronavirus pandemic that
both Nick and I, I’m sure, will have a lot to say about next time we speak, and perhaps
that is for the best, because the deepest lessons can be learned only in retrospect
when the storm has passed.
I do recommend you read many of his papers on the topic of existential risk, including
the technical report titled Global Catastrophic Risks Survey that he coauthored with Anders
For everyone feeling the medical, psychological, and financial burden of this crisis, I’m
sending love your way.
We’re in this together.
We’ll beat this thing.
This is the Artificial Intelligence Podcast.
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it on Patreon, or simply connect with me on Twitter at Lex Friedman, spelled F R I D M
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And now, here’s my conversation with Nick Bostrom.
At the risk of asking the Beatles to play yesterday or the Rolling Stones to play Satisfaction,
let me ask you the basics.
What is the simulation hypothesis?
That we are living in a computer simulation.
What is a computer simulation?
How are we supposed to even think about that?
Well, so the hypothesis is meant to be understood in a literal sense, not that we can kind of
metaphorically view the universe as an information processing physical system, but that there
is some advanced civilization who built a lot of computers and that what we experience
is an effect of what’s going on inside one of those computers so that the world around
us, our own brains, everything we see and perceive and think and feel would exist because
this computer is running certain programs.
So do you think of this computer as something similar to the computers of today, these deterministic
sort of Turing machine type things?
Is that what we’re supposed to imagine or we’re supposed to think of something more
like a quantum mechanical system?
Something much bigger, something much more complicated, something much more mysterious
from our current perspective?
The ones we have today would do fine, I mean, bigger, certainly.
You’d need more memory and more processing power.
I don’t think anything else would be required.
Now, it might well be that they do have additional, maybe they have quantum computers and other
things that would give them even more of, it seems kind of plausible, but I don’t think
it’s a necessary assumption in order to get to the conclusion that a technologically
mature civilization would be able to create these kinds of computer simulations with conscious
beings inside them.
So do you think the simulation hypothesis is an idea that’s most useful in philosophy,
computer science, physics, sort of where do you see it having valuable kind of starting
point in terms of a thought experiment of it?
Is it useful?
I guess it’s more informative and interesting and maybe important, but it’s not designed
to be useful for something else.
Okay, interesting, sure.
But is it philosophically interesting or is there some kind of implications of computer
science and physics?
I think not so much for computer science or physics per se.
Certainly it would be of interest in philosophy, I think also to say cosmology or physics in
as much as you’re interested in the fundamental building blocks of the world and the rules
that govern it.
If we are in a simulation, there is then the possibility that say physics at the level
where the computer running the simulation could be different from the physics governing
phenomena in the simulation.
So I think it might be interesting from point of view of religion or just for kind of trying
to figure out what the heck is going on.
So we mentioned the simulation hypothesis so far.
There is also the simulation argument, which I tend to make a distinction.
So simulation hypothesis, we are living in a computer simulation.
Simulation argument, this argument that tries to show that one of three propositions is
true, one of which is the simulation hypothesis, but there are two alternatives in the original
simulation argument, which we can get to.
Yeah, let’s go there.
By the way, confusing terms because people will, I think, probably naturally think simulation
argument equals simulation hypothesis, just terminology wise.
But let’s go there.
So simulation hypothesis means that we are living in a simulations, the hypothesis that
we’re living in a simulation, simulation argument has these three complete possibilities that
cover all possibilities.
So what are they?
So it’s like a disjunction.
It says at least one of these three is true, although it doesn’t on its own tell us which
So the first one is that almost all civilizations that are current stage of technological development
go extinct before they reach technological maturity.
So there is some great filter that makes it so that basically none of the civilizations
throughout maybe a vast cosmos will ever get to realize the full potential of technological
And this could be, theoretically speaking, this could be because most civilizations kill
themselves too eagerly or destroy themselves too eagerly, or it might be super difficult
to build a simulation.
So the span of time.
Theoretically it could be both.
Now I think it looks like we would technologically be able to get there in a time span that
is short compared to, say, the lifetime of planets and other sort of astronomical processes.
So your intuition is to build a simulation is not…
Well, so this is interesting concept of technological maturity.
It’s kind of an interesting concept to have other purposes as well.
We can see even based on our current limited understanding what some lower bound would
be on the capabilities that you could realize by just developing technologies that we already
see are possible.
So for example, one of my research fellows here, Eric Drexler, back in the 80s, studied
That is you could analyze using theoretical tools and computer modeling the performance
of various molecularly precise structures that we didn’t then and still don’t today
have the ability to actually fabricate.
But you could say that, well, if we could put these atoms together in this way, then
the system would be stable and it would rotate at this speed and have all these computational
And he also outlined some pathways that would enable us to get to this kind of molecularly
manufacturing in the fullness of time.
And you could do other studies we’ve done.
You could look at the speed at which, say, it would be possible to colonize the galaxy
if you had mature technology.
We have an upper limit, which is the speed of light.
We have sort of a lower current limit, which is how fast current rockets go.
We know we can go faster than that by just making them bigger and have more fuel and
We can then start to describe the technological affordances that would exist once a civilization
has had enough time to develop, at least those technologies we already know are possible.
Then maybe they would discover other new physical phenomena as well that we haven’t realized
that would enable them to do even more.
But at least there is this kind of basic set of capabilities.
Can you just link on that, how do we jump from molecular manufacturing to deep space
exploration to mature technology?
What’s the connection there?
Well, so these would be two examples of technological capability sets that we can have a high degree
of confidence are physically possible in our universe and that a civilization that was
allowed to continue to develop its science and technology would eventually attain.
You can intuit like, we can kind of see the set of breakthroughs that are likely to happen.
So you can see like, what did you call it, the technological set?
With computers, maybe it’s easiest.
One is we could just imagine bigger computers using exactly the same parts that we have.
So you can kind of scale things that way, right?
But you could also make processors a bit faster.
If you had this molecular nanotechnology that Eric Drexler described, he characterized a
kind of crude computer built with these parts that would perform at a million times the
human brain while being significantly smaller, the size of a sugar cube.
And he made no claim that that’s the optimum computing structure, like for all you know,
we could build faster computers that would be more efficient, but at least you could
do that if you had the ability to do things that were atomically precise.
I mean, so you can then combine these two.
You could have this kind of nanomolecular ability to build things atom by atom and then
say at this as a spatial scale that would be attainable through space colonizing technology.
You could then start, for example, to characterize a lower bound on the amount of computing power
that a technologically mature civilization would have.
If it could grab resources, you know, planets and so forth, and then use this molecular
nanotechnology to optimize them for computing, you’d get a very, very high lower bound on
the amount of compute.
So sorry, just to define some terms, so technologically mature civilization is one that took that
piece of technology to its lower bound.
What is a technologically mature civilization?
So that means it’s a stronger concept than we really need for the simulation hypothesis.
I just think it’s interesting in its own right.
So it would be the idea that there is some stage of technological development where you’ve
basically maxed out, that you developed all those general purpose, widely useful technologies
that could be developed, or at least kind of come very close to the, you know, 99.9%
there or something.
So that’s an independent question.
You can think either that there is such a ceiling, or you might think it just goes,
the technology tree just goes on forever.
Where does your sense fall?
I would guess that there is a maximum that you would start to asymptote towards.
So new things won’t keep springing up, new ceilings.
In terms of basic technological capabilities, I think that, yeah, there is like a finite
set of laws that can exist in this universe.
Moreover, I mean, I wouldn’t be that surprised if we actually reached close to that level
fairly shortly after we have, say, machine superintelligence.
So I don’t think it would take millions of years for a human originating civilization
to begin to do this.
It’s more likely to happen on historical timescales.
But that’s an independent speculation from the simulation argument.
I mean, for the purpose of the simulation argument, it doesn’t really matter whether
it goes indefinitely far up or whether there is a ceiling, as long as we know we can at
least get to a certain level.
And it also doesn’t matter whether that’s going to happen in 100 years or 5,000 years
or 50 million years.
Like the timescales really don’t make any difference for this.
Can you look on that a little bit?
Like there’s a big difference between 100 years and 10 million years.
So it doesn’t really not matter because you just said it doesn’t matter if we jump scales
to beyond historical scales.
So we described that.
So for the simulation argument, sort of doesn’t it matter that we if it takes 10 million years,
it gives us a lot more opportunity to destroy civilization in the meantime?
Yeah, well, so it would shift around the probabilities between these three alternatives.
That is, if we are very, very far away from being able to create these simulations, if
it’s like, say, billions of years into the future, then it’s more likely that we will
fail ever to get there.
There’s more time for us to kind of go extinct along the way.
And so this is similarly for other civilizations.
So it is important to think about how hard it is to build a simulation.
In terms of figuring out which of the disjuncts.
But for the simulation argument itself, which is agnostic as to which of these three alternatives
It’s like you don’t have to like the simulation argument would be true whether or not we thought
this could be done in 500 years or it would take 500 million years.
No, for sure.
The simulation argument stands.
I mean, I’m sure there might be some people who oppose it, but it doesn’t matter.
I mean, it’s very nice those three cases cover it.
But the fun part is at least not saying what the probabilities are, but kind of thinking
about kind of intuiting reasoning about what’s more likely, what are the kind of things that
would make some of the arguments less and more so like.
But let’s actually, I don’t think we went through them.
So number one is we destroy ourselves before we ever create simulation.
So that’s kind of sad, but we have to think not just what might destroy us.
I mean, so there could be some whatever disaster, some meteor slamming the earth a few years
from now that could destroy us.
But you’d have to postulate in order for this first disjunct to be true that almost all
civilizations throughout the cosmos also failed to reach technological maturity.
And the underlying assumption there is that there is likely a very large number of other
Well, if there are, yeah, then they would virtually all have to succumb in the same
I mean, then that leads off another, I guess there are a lot of little digressions that
Definitely, let’s go there.
Let’s go there.
Keep dragging us back.
Well, there are these, there is a set of basic questions that always come up in conversations
with interesting people, like the Fermi paradox, like there’s like, you could almost define
whether a person is interesting, whether at some point the question of the Fermi paradox
comes up, like, well, so for what it’s worth, it looks to me that the universe is very big.
I mean, in fact, according to the most popular current cosmological theories, infinitely
And so then it would follow pretty trivially that it would contain a lot of other civilizations,
in fact, infinitely many.
If you have some local stochasticity and infinitely many, it’s like, you know, infinitely many
lumps of matter, one next to another, there’s kind of random stuff in each one, then you’re
going to get all possible outcomes with probability one infinitely repeated.
So then certainly there would be a lot of extraterrestrials out there.
Even short of that, if the universe is very big, that might be a finite but large number.
If we were literally the only one, yeah, then of course, if we went extinct, then all of
civilizations at our current stage would have gone extinct before becoming technological
So then it kind of becomes trivially true that a very high fraction of those went extinct.
But if we think there are many, I mean, it’s interesting, because there are certain things
that possibly could kill us, like if you look at existential risks, and it might be a different,
like the best answer to what would be most likely to kill us might be a different answer
than the best answer to the question, if there is something that kills almost everyone, what
would that be?
Because that would have to be some risk factor that was kind of uniform overall possible
So in this, for the sake of this argument, you have to think about not just us, but like
every civilization dies out before they create the simulation or something very close to
So what’s number two in the number two is the convergence hypothesis that is that maybe
like a lot of some of these civilizations do make it through to technological maturity,
but out of those who do get there, they all lose interest in creating these simulations.
So they just have the capability of doing it, but they choose not to.
Not just a few of them decide not to, but out of a million, maybe not even a single
one of them would do it.
And I think when you say lose interest, that sounds like unlikely because it’s like they
get bored or whatever, but it could be so many possibilities within that.
I mean, losing interest could be, it could be anything from it being exceptionally difficult
to do to fundamentally changing the sort of the fabric of reality.
If you do it is ethical concerns, all those kinds of things could be exceptionally strong
Well, certainly, I mean, yeah, ethical concerns.
I mean, not really too difficult to do.
I mean, in a sense, that’s the first assumption that you get to technological maturity where
you would have the ability using only a tiny fraction of your resources to create many,
So it wouldn’t be the case that they would need to spend half of their GDP forever in
order to create one simulation and they had this like difficult debate about whether they
should invest half of their GDP for this.
It would more be like, well, if any little fraction of the civilization feels like doing
this at any point during maybe their millions of years of existence, then that would be
millions of simulations.
But certainly, there could be many conceivable reasons for why there would be this convert,
many possible reasons for not running ancestor simulations or other computer simulations,
even if you could do so cheaply.
By the way, what’s an ancestor simulation?
Well, that would be the type of computer simulation that would contain people like those we think
have lived on our planet in the past and like ourselves in terms of the types of experiences
they have and where those simulated people are conscious.
So like not just simulated in the same sense that a non player character would be simulated
in the current computer game where it’s kind of has like an avatar body and then a very
simple mechanism that moves it forward or backwards.
But something where the simulated being has a brain, let’s say that’s simulated at a sufficient
level of granularity that it would have the same subjective experiences as we have.
So where does consciousness fit into this?
Do you think simulation, I guess there are different ways to think about how this can
be simulated, just like you’re talking about now.
Do we have to simulate each brain within the larger simulation?
Is it enough to simulate just the brain, just the minds and not the simulation, not the
Like, is there a different ways to think about this?
Yeah, I guess there is a kind of premise in the simulation argument rolled in from philosophy
of mind that is that it would be possible to create a conscious mind in a computer.
And that what determines whether some system is conscious or not is not like whether it’s
built from organic biological neurons, but maybe something like what the structure of
the computation is that it implements.
So we can discuss that if we want, but I think it would be more forward as far as my view
that it would be sufficient, say, if you had a computation that was identical to the computation
in the human brain down to the level of neurons.
So if you had a simulation with 100 billion neurons connected in the same way as the human
brain, and you then roll that forward with the same kind of synaptic weights and so forth,
so you actually had the same behavior coming out of this as a human with that brain would
have done, then I think that would be conscious.
Now it’s possible you could also generate consciousness without having that detailed
assimilation, there I’m getting more uncertain exactly how much you could simplify or abstract
Can you look on that?
What do you mean?
I missed where you’re placing consciousness in the second.
Well, so if you are a computationalist, do you think that what creates consciousness
is the implementation of a computation?
Some property, emergent property of the computation itself.
That’s the idea.
Yeah, you could say that.
But then the question is, what’s the class of computations such that when they are run,
So if you just have something that adds one plus one plus one plus one, like a simple
computation, you think maybe that’s not going to have any consciousness.
If on the other hand, the computation is one like our human brains are performing, where
as part of the computation, there is a global workspace, a sophisticated attention mechanism,
there is self representations of other cognitive processes and a whole lot of other things
that possibly would be conscious.
And in fact, if it’s exactly like ours, I think definitely it would.
But exactly how much less than the full computation that the human brain is performing would be
required is a little bit, I think, of an open question.
He asked another interesting question as well, which is, would it be sufficient to just have
say the brain or would you need the environment in order to generate the same kind of experiences
that we have?
And there is a bunch of stuff we don’t know.
I mean, if you look at, say, current virtual reality environments, one thing that’s clear
is that we don’t have to simulate all details of them all the time in order for, say, the
human player to have the perception that there is a full reality and that you can have say
procedurally generated where you might only render a scene when it’s actually within the
view of the player character.
And so similarly, if this environment that we perceive is simulated, it might be that
all of the parts that come into our view are rendered at any given time.
And a lot of aspects that never come into view, say the details of this microphone I’m
talking into, exactly what each atom is doing at any given point in time, might not be part
of the simulation, only a more coarse grained representation.
So that to me is actually from an engineering perspective, why the simulation hypothesis
is really interesting to think about is how difficult is it to fake sort of in a virtual
reality context, I don’t know if fake is the right word, but to construct a reality that
is sufficiently real to us to be immersive in the way that the physical world is.
I think that’s actually probably an answerable question of psychology, of computer science,
of how, where’s the line where it becomes so immersive that you don’t want to leave
Yeah, or that you don’t realize while you’re in it that it is a virtual world.
Yeah, those are two actually questions, yours is the more sort of the good question about
the realism, but mine, from my perspective, what’s interesting is it doesn’t have to be
real, but how can we construct a world that we wouldn’t want to leave?
Yeah, I mean, I think that might be too low a bar, I mean, if you think, say when people
first had pong or something like that, I’m sure there were people who wanted to keep
playing it for a long time because it was fun and they wanted to be in this little world.
I’m not sure we would say it’s immersive, I mean, I guess in some sense it is, but like
an absorbing activity doesn’t even have to be.
But they left that world though, that’s the thing.
So like, I think that bar is deceivingly high.
So they eventually left, so you can play pong or Starcraft or whatever more sophisticated
games for hours, for months, you know, while the work has to be in a big addiction, but
eventually they escaped that.
So you mean when it’s absorbing enough that you would spend your entire, you would choose
to spend your entire life in there.
And then thereby changing the concept of what reality is, because your reality becomes the
Not because you’re fooled, but because you’ve made that choice.
Yeah, and it made, different people might have different preferences regarding that.
Some might, even if you had any perfect virtual reality, might still prefer not to spend the
rest of their lives there.
I mean, in philosophy, there’s this experience machine, thought experiment.
Have you come across this?
So Robert Nozick had this thought experiment where you imagine some crazy super duper neuroscientist
of the future have created a machine that could give you any experience you want if
you step in there.
And for the rest of your life, you can kind of pre programmed it in different ways.
So your fun dreams could come true, you could, whatever you dream, you want to be a great
artist, a great lover, like have a wonderful life, all of these things.
If you step into the experience machine will be your experiences, constantly happy.
But you would kind of disconnect from the rest of reality and you would float there
in a tank.
And so Nozick thought that most people would choose not to enter the experience machine.
I mean, many might want to go there for a holiday, but they wouldn’t want to have to
check out of existence permanently.
And so he thought that was an argument against certain views of value according to what we
value is a function of what we experience.
Because in the experience machine, you could have any experience you want, and yet many
people would think that would not be much value.
So therefore, what we value depends on other things than what we experience.
So okay, can you can you take that argument further?
What about the fact that maybe what we value is the up and down of life?
So you could have up and downs in the experience machine, right?
But what can’t you have in the experience machine?
Well, I mean, that then becomes an interesting question to explore.
But for example, real connection with other people, if the experience machine is a solo
machine where it’s only you, like that’s something you wouldn’t have there.
You would have this subjective experience that would be like fake people.
But when if you gave somebody flowers, there wouldn’t be anybody there who actually got
It would just be a little simulation of somebody smiling.
But the simulation would not be the kind of simulation I’m talking about in the simulation
argument where the simulated creature is conscious, it would just be a kind of smiley face that
would look perfectly real to you.
So we’re now drawing a distinction between appear to be perfectly real and actually being
Um, so that could be one thing, I mean, like a big impact on history, maybe is also something
you won’t have if you check into this experience machine.
So some people might actually feel the life I want to have for me is one where I have
a big positive impact on history unfolds.
So you could kind of explore these different possible explanations for why it is you wouldn’t
want to go into the experience machine if that’s, if that’s what you feel.
And one interesting observation regarding this Nozick thought experiment and the conclusions
he wanted to draw from it is how much is a kind of a status quo effect.
So a lot of people might not want to get this on current reality to plug into this dream
But if they instead were told, well, what you’ve experienced up to this point was a
dream now, do you want to disconnect from this and enter the real world when you have
no idea maybe what the real world is, or maybe you could say, well, you’re actually a farmer
in Peru, growing, you know, peanuts, and you could live for the rest of your life in this
way, or would you want to continue your dream life as Alex Friedman going around the world
making podcasts and doing research.
So if the status quo was that they were actually in the experience machine, I think a lot of
people might then prefer to live the life that they are familiar with rather than sort
of bail out into.
So that’s interesting, the change itself, the leap, yeah, so it might not be so much
the reality itself that we’re after.
But it’s more that we are maybe involved in certain projects and relationships.
And we have, you know, a self identity and these things that our values are kind of connected
with carrying that forward.
And then whether it’s inside a tank or outside a tank in Peru, or whether inside a computer
outside a computer, that’s kind of less important to what we ultimately care about.
Yeah, but still, so just to linger on it, it is interesting.
I find maybe people are different, but I find myself quite willing to take the leap to the
farmer in Peru, especially as the virtual reality system become more realistic.
I find that possibility and I think more people would take that leap.
But so in this thought experiment, just to make sure we are understanding, so in this
case, the farmer in Peru would not be a virtual reality, that would be the real, your life,
like before this whole experience machine started.
Well, I kind of assumed from that description, you’re being very specific, but that kind
of idea just like washes away the concept of what’s real.
I’m still a little hesitant about your kind of distinction between real and illusion.
Because when you can have an illusion that feels, I mean, that looks real, I don’t know
how you can definitively say something is real or not, like what’s a good way to prove
that something is real in that context?
Well, so I guess in this case, it’s more a stipulation.
In one case, you’re floating in a tank with these wires by the super duper neuroscientists
plugging into your head, giving you like Friedman experiences.
In the other, you’re actually tilling the soil in Peru, growing peanuts, and then those
peanuts are being eaten by other people all around the world who buy the exports.
That’s two different possible situations in the one and the same real world that you could
choose to occupy.
But just to be clear, when you’re in a vat with wires and the neuroscientists, you can
still go farming in Peru, right?
No, well, if you wanted to, you could have the experience of farming in Peru, but there
wouldn’t actually be any peanuts grown.
But what makes a peanut, so a peanut could be grown and you could feed things with that
peanut and why can’t all of that be done in a simulation?
I hope, first of all, that they actually have peanut farms in Peru, I guess we’ll get a
lot of comments otherwise from Angrit.
I was way up to the point when you started talking about Peru peanuts, that’s when I
realized you’re relying out of these.
In that climate.
No, I mean, I think, I mean, in the simulation, I think there is a sense, the important sense
in which it would all be real.
Nevertheless, there is a distinction between inside the simulation and outside the simulation.
Or in the case of Nozick’s thought experiment, whether you’re in the vat or outside the vat,
and some of those differences may or may not be important.
I mean, that comes down to your values and preferences.
So if the, if the experience machine only gives you the experience of growing peanuts,
but you’re the only one in the experience machines.
No, but there’s other, you can, within the experience machine, others can plug in.
Well, there are versions of the experience machine.
So in fact, you might want to have, distinguish different thought experiments, different versions
So in, like in the original thought experiment, maybe it’s only you, right?
And you think, I wouldn’t want to go in there.
Well, that tells you something interesting about what you value and what you care about.
Then you could say, well, what if you add the fact that there would be other people
in there and you would interact with them?
Well, it starts to make it more attractive, right?
Then you could add in, well, what if you could also have important longterm effects on human
history and the world, and you could actually do something useful, even though you were
That makes it maybe even more attractive.
Like you could actually have a life that had a purpose and consequences.
And so as you sort of add more into it, it becomes more similar to the baseline reality
that you were comparing it to.
Yeah, but I just think inside the experience machine and without taking those steps you
just mentioned, you still have an impact on longterm history of the creatures that live
inside that, of the quote unquote fake creatures that live inside that experience machine.
And that, like at a certain point, you know, if there’s a person waiting for you inside
that experience machine, maybe your newly found wife and she dies, she has fear, she
has hopes, and she exists in that machine when you plug out, when you unplug yourself
and plug back in, she’s still there going on about her life.
Well, in that case, yeah, she starts to have more of an independent existence.
But it depends, I think, on how she’s implemented in the experience machine.
Take one limit case where all she is is a static picture on the wall, a photograph.
So you think, well, I can look at her, right?
But that’s it.
Then you think, well, it doesn’t really matter much what happens to that, any more than a
normal photograph if you tear it up, right?
It means you can’t see it anymore, but you haven’t harmed the person whose picture you
But if she’s actually implemented, say, at a neural level of detail so that she’s a fully
realized digital mind with the same behavioral repertoire as you have, then very plausibly
she would be a conscious person like you are.
And then what you do in this experience machine would have real consequences for how this
other mind felt.
So you have to specify which of these experience machines you’re talking about.
I think it’s not entirely obvious that it would be possible to have an experience machine
that gave you a normal set of human experiences, which include experiences of interacting with
other people, without that also generating consciousnesses corresponding to those other
That is, if you create another entity that you perceive and interact with, that to you
looks entirely realistic.
Not just when you say hello, they say hello back, but you have a rich interaction, many
days, deep conversations.
It might be that the only possible way of implementing that would be one that also has
a side effect, instantiated this other person in enough detail that you would have a second
I think that’s to some extent an open question.
So you don’t think it’s possible to fake consciousness and fake intelligence?
Well, it might be.
I mean, I think you can certainly fake, if you have a very limited interaction with somebody,
you could certainly fake that.
If all you have to go on is somebody said hello to you, that’s not enough for you to
tell whether that was a real person there, or a prerecorded message, or a very superficial
simulation that has no consciousness, because that’s something easy to fake.
We could already fake it, now you can record a voice recording.
But if you have a richer set of interactions where you’re allowed to ask open ended questions
and probe from different angles, you couldn’t give canned answer to all of the possible
ways that you could probe it, then it starts to become more plausible that the only way
to realize this thing in such a way that you would get the right answer from any which
angle you probed it, would be a way of instantiating it, where you also instantiated a conscious
Yeah, I’m with you on the intelligence part, but is there something about me that says
consciousness is easier to fake?
Like I’ve recently gotten my hands on a lot of rubas, don’t ask me why or how.
And I’ve made them, there’s just a nice robotic mobile platform for experiments.
And I made them scream and or moan in pain, so on, just to see when they’re responding
And it’s just a sort of psychological experiment on myself.
And I think they appear conscious to me pretty quickly.
To me, at least my brain can be tricked quite easily.
I said if I introspect, it’s harder for me to be tricked that something is intelligent.
So I just have this feeling that inside this experience machine, just saying that you’re
conscious and having certain qualities of the interaction, like being able to suffer,
like being able to hurt, like being able to wander about the essence of your own existence,
not actually, I mean, creating the illusion that you’re wandering about it is enough to
create the illusion of consciousness.
And because of that, create a really immersive experience to where you feel like that is
the real world.
So you think there’s a big gap between appearing conscious and being conscious?
Or is it that you think it’s very easy to be conscious?
I’m not actually sure what it means to be conscious.
All I’m saying is the illusion of consciousness is enough to create a social interaction that’s
as good as if the thing was conscious, meaning I’m making it about myself.
I mean, I guess there are a few different things.
One is how good the interaction is, which might, I mean, if you don’t really care about
like probing hard for whether the thing is conscious, maybe it would be a satisfactory
interaction, whether or not you really thought it was conscious.
Now, if you really care about it being conscious in like inside this experience machine, how
easy would it be to fake it?
And you say, it sounds fairly easy, but then the question is, would that also mean it’s
very easy to instantiate consciousness?
Like it’s much more widely spread in the world and we have thought it doesn’t require a big
human brain with a hundred billion neurons, all you need is some system that exhibits
basic intentionality and can respond and you already have consciousness.
Like in that case, I guess you still have a close coupling.
I guess that case would be where they can come apart, where you could create the appearance
of there being a conscious mind with actually not being another conscious mind.
I’m somewhat agnostic exactly where these lines go.
I think one observation that makes it plausible that you could have very realistic appearances
relatively simply, which also is relevant for the simulation argument and in terms of
thinking about how realistic would a virtual reality model have to be in order for the
simulated creature not to notice that anything was awry.
Well, just think of our own humble brains during the wee hours of the night when we
Many times, well, dreams are very immersive, but often you also don’t realize that you’re
in a dream.
And that’s produced by simple primitive three pound lumps of neural matter effortlessly.
So if a simple brain like this can create the virtual reality that seems pretty real
to us, then how much easier would it be for a super intelligent civilization with planetary
sized computers optimized over the eons to create a realistic environment for you to
By the way, behind that intuition is that our brain is not that impressive relative
to the possibilities of what technology could bring.
It’s also possible that the brain is the epitome, is the ceiling.
How is that possible?
Meaning like this is the smartest possible thing that the universe could create.
So that seems unlikely to me.
I mean, for some of these reasons we alluded to earlier in terms of designs we already
have for computers that would be faster by many orders of magnitude than the human brain.
We can see that the constraints, the cognitive constraints in themselves is what enables
So the more powerful you make the computer, the less likely it is to become super intelligent.
This is where I say dumb things to push back on that statement.
I’m not sure I thought that we might.
I mean, so there are different dimensions of intelligence.
A simple one is just speed.
Like if you can solve the same challenge faster in some sense, you’re like smarter.
So there I think we have very strong evidence for thinking that you could have a computer
in this universe that would be much faster than the human brain and therefore have speed
super intelligence, like be completely superior, maybe a million times faster.
Then maybe there are other ways in which you could be smarter as well, maybe more qualitative
And the concepts are a little bit less clear cut.
So it’s harder to make a very crisp, neat, firmly logical argument for why that could
be qualitative super intelligence as opposed to just things that were faster.
Although I still think it’s very plausible and for various reasons that are less than
But when you can sort of, for example, if you look at animals and even within humans,
like there seems to be like Einstein versus random person, like it’s not just that Einstein
was a little bit faster, but like how long would it take a normal person to invent general
relativity is like, it’s not 20% longer than it took Einstein or something like that.
It’s like, I don’t know whether they would do it at all or it would take millions of
years or some totally bizarre.
But your intuition is that the compute size will get you go increasing the size of the
computer and the speed of the computer might create some much more powerful levels of intelligence
that would enable some of the things we’ve been talking about with like the simulation,
being able to simulate an ultra realistic environment, ultra realistic perception of
I mean, strictly speaking, it would not be necessary to have super intelligence in order
to have say the technology to make these simulations, ancestor simulations or other kinds of simulations.
As a matter of fact, I think if we are in a simulation, it would most likely be one
built by a civilization that had super intelligence.
It certainly would help a lot.
I mean, you could build more efficient larger scale structures if you had super intelligence.
I also think that if you had the technology to build these simulations, that’s like a
very advanced technology.
It seems kind of easier to get the technology to super intelligence.
I’d expect by the time they could make these fully realistic simulations of human history
with human brains in there, like before that they got to that stage, they would have figured
out how to create machine super intelligence or maybe biological enhancements of their
own brains if there were biological creatures to start with.
So we talked about the three parts of the simulation argument.
One, we destroy ourselves before we ever create the simulation.
Two, we somehow, everybody somehow loses interest in creating the simulation.
Three, we’re living in a simulation.
So you’ve kind of, I don’t know if your thinking has evolved on this point, but you kind of
said that we know so little that these three cases might as well be equally probable.
So probabilistically speaking, where do you stand on this?
Yeah, I mean, I don’t think equal necessarily would be the most supported probability assignment.
So how would you, without assigning actual numbers, what’s more or less likely in your
Well, I mean, I’ve historically tended to punt on the question of like between these
So maybe you ask me another way is which kind of things would make each of these more or
What kind of intuition?
Certainly in general terms, if you think anything that say increases or reduces the probability
of one of these, we tend to slosh probability around on the other.
So if one becomes less probable, like the other would have to, cause it’s got to add
up to one.
So if we consider the first hypothesis, the first alternative that there’s this filter
that makes it so that virtually no civilization reaches technological maturity, in particular
our own civilization, if that’s true, then it’s like very unlikely that we would reach
technological maturity because if almost no civilization at our stage does it, then it’s
unlikely that we do it.
Sorry, can you linger on that for a second?
Well, so if it’s the case that almost all civilizations at our current stage of technological
development failed to reach maturity, that would give us very strong reason for thinking
we will fail to reach technological maturity.
Oh, and also sort of the flip side of that is the fact that we’ve reached it means that
many other civilizations have reached this point.
So that means if we get closer and closer to actually reaching technological maturity,
there’s less and less distance left where we could go extinct before we are there, and
therefore the probability that we will reach increases as we get closer, and that would
make it less likely to be true that almost all civilizations at our current stage failed
to get there.
Like we would have this…
The one case we had started ourselves would be very close to getting there, that would
be strong evidence that it’s not so hard to get to technological maturity.
So to the extent that we feel we are moving nearer to technological maturity, that would
tend to reduce the probability of the first alternative and increase the probability of
the other two.
It doesn’t need to be a monotonic change.
Like if every once in a while some new threat comes into view, some bad new thing you could
do with some novel technology, for example, that could change our probabilities in the
But that technology, again, you have to think about as that technology has to be able to
equally in an even way affect every civilization out there.
Yeah, pretty much.
I mean, that’s strictly speaking, it’s not true.
I mean, that could be two different existential risks and every civilization, you know, one
or the other, like, but none of them kills more than 50%.
But incidentally, so in some of my work, I mean, on machine superintelligence, like pointed
to some existential risks related to sort of super intelligent AI and how we must make
sure, you know, to handle that wisely and carefully.
It’s not the right kind of existential catastrophe to make the first alternative true though.
Like it might be bad for us if the future lost a lot of value as a result of it being
shaped by some process that optimized for some completely nonhuman value.
But even if we got killed by machine superintelligence, that machine superintelligence might still
attain technological maturity.
Oh, I see, so you’re not human exclusive.
This could be any intelligent species that achieves, like it’s all about the technological
But the humans have to attain it.
So like superintelligence could replace us and that’s just as well for the simulation
I mean, it could interact with the second hypothesis by alternative.
Like if the thing that replaced us was either more likely or less likely than we would be
to have an interest in creating ancestor simulations, you know, that could affect probabilities.
But yeah, to a first order, like if we all just die, then yeah, we won’t produce any
simulations because we are dead.
But if we all die and get replaced by some other intelligent thing that then gets to
technological maturity, the question remains, of course, if not that thing, then use some
of its resources to do this stuff.
So can you reason about this stuff, given how little we know about the universe?
Is it reasonable to reason about these probabilities?
So like how little, well, maybe you can disagree, but to me, it’s not trivial to figure out
how difficult it is to build a simulation.
We kind of talked about it a little bit.
We also don’t know, like as we try to start building it, like start creating virtual worlds
and so on, how that changes the fabric of society.
Like there’s all these things along the way that can fundamentally change just so many
aspects of our society about our existence that we don’t know anything about, like the
kind of things we might discover when we understand to a greater degree the fundamental, the physics,
like the theory, if we have a breakthrough, have a theory and everything, how that changes
stuff, how that changes deep space exploration and so on.
Like, is it still possible to reason about probabilities given how little we know?
Yes, I think there will be a large residual of uncertainty that we’ll just have to acknowledge.
And I think that’s true for most of these big picture questions that we might wonder
It’s just we are small, short lived, small brained, cognitively very limited humans with
And it’s amazing we can figure out as much as we can really about the cosmos.
But okay, so there’s this cognitive trick that seems to happen when I look at the simulation
argument, which for me, it seems like case one and two feel unlikely.
I want to say feel unlikely as opposed to sort of like, it’s not like I have too much
scientific evidence to say that either one or two are not true.
It just seems unlikely that every single civilization destroys itself.
And it seems like feels unlikely that the civilizations lose interest.
So naturally, without necessarily explicitly doing it, but the simulation argument basically
says it’s very likely we’re living in a simulation.
To me, my mind naturally goes there.
I think the mind goes there for a lot of people.
Is that the incorrect place for it to go?
Well, not necessarily.
I think the second alternative, which has to do with the motivations and interests of
technological and material civilizations, I think there is much we don’t understand about
Can you talk about that a little bit?
What do you think?
I mean, this is a question that pops up when you when you build an AGI system or build
a general intelligence.
How does that change our motivations?
Do you think it’ll fundamentally transform our motivations?
Well, it doesn’t seem that implausible that once you take this leap to to technological
maturity, I mean, I think like it involves creating machine super intelligence, possibly
that would be sort of on the path for basically all civilizations, maybe before they are able
to create large numbers of ancestry simulations, they would that that possibly could be one
of these things that quite radically changes the orientation of what a civilization is,
in fact, optimizing for.
There are other things as well.
So at the moment, we have not perfect control over our own being our own mental states,
our own experiences are not under our direct control.
So for example, if if you want to experience a pleasure and happiness, you might have to
do a whole host of things in the external world to try to get into the stage into the
mental state where you experience pleasure, like some people get some pleasure from eating
Well, they can just turn that on, they have to kind of actually go to a nice restaurant
and then they have to make money.
So there’s like all this kind of activity that maybe arises from the fact that we are
trying to ultimately produce mental states.
But the only way to do that is by a whole host of complicated activities in the external
Now, at some level of technological development, I think we’ll become auto potent in the sense
of gaining direct ability to choose our own internal configuration, and enough knowledge
and insight to be able to actually do that in a meaningful way.
So then it could turn out that there are a lot of instrumental goals that would drop
out of the picture and be replaced by other instrumental goals, because we could now serve
some of these final goals in more direct ways.
And who knows how all of that shakes out after civilizations reflect on that and converge
on different attractors and so on and so forth.
And that could be new instrumental considerations that come into view as well, that we are just
oblivious to, that would maybe have a strong shaping effect on actions, like very strong
reasons to do something or not to do something, then we just don’t realize they are there
because we are so dumb, bumbling through the universe.
But if almost inevitably en route to attaining the ability to create many ancestors simulations,
you do have this cognitive enhancement, or advice from super intelligences or yourself,
then maybe there’s like this additional set of considerations coming into view and it’s
obvious that the thing that makes sense is to do X, whereas right now it seems you could
X, Y or Z and different people will do different things and we are kind of random in that sense.
Because at this time, with our limited technology, the impact of our decisions is minor.
I mean, that’s starting to change in some ways.
Well, I’m not sure how it follows that the impact of our decisions is minor.
Well, it’s starting to change.
I mean, I suppose 100 years ago it was minor.
It’s starting to…
Well, it depends on how you view it.
What people did 100 years ago still have effects on the world today.
Oh, I see.
As a civilization in the togetherness.
So it might be that the greatest impact of individuals is not at technological maturity
or very far down.
It might be earlier on when there are different tracks, civilization could go down.
Maybe the population is smaller, things still haven’t settled out.
If you count indirect effects, those could be bigger than the direct effects that people
have later on.
So part three of the argument says that…
So that leads us to a place where eventually somebody creates a simulation.
I think you had a conversation with Joe Rogan.
I think there’s some aspect here where you got stuck a little bit.
How does that lead to we’re likely living in a simulation?
So this kind of probability argument, if somebody eventually creates a simulation, why does
that mean that we’re now in a simulation?
What you get to if you accept alternative three first is there would be more simulated
people with our kinds of experiences than non simulated ones.
Like if you look at the world as a whole, by the end of time as it were, you just count
That would be more simulated ones than non simulated ones.
Then there is an extra step to get from that.
If you assume that, suppose for the sake of the argument, that that’s true.
How do you get from that to the statement we are probably in a simulation?
So here you’re introducing an indexical statement like it’s that this person right now is in
There are all these other people that are in simulations and some that are not in the
But what probability should you have that you yourself is one of the simulated ones
in that setup?
So I call it the bland principle of indifference, which is that in cases like this, when you
have two sets of observers, one of which is much larger than the other and you can’t from
any internal evidence you have, tell which set you belong to, you should assign a probability
that’s proportional to the size of these sets.
So that if there are 10 times more simulated people with your kinds of experiences, you
would be 10 times more likely to be one of those.
Is that as intuitive as it sounds?
I mean, that seems kind of, if you don’t have enough information, you should rationally
just assign the same probability as the size of the set.
It seems pretty plausible to me.
Where are the holes in this?
Is it at the very beginning, the assumption that everything stretches, you have infinite
You don’t need infinite time.
You just need, how long does the time take?
However long it takes, I guess, for a universe to produce an intelligent civilization that
attains the technology to run some ancestry simulations.
When the first simulation is created, that stretch of time, just a little longer than
they’ll all start creating simulations.
Well, I mean, there might be a difference.
If you think of there being a lot of different planets and some subset of them have life
and then some subset of those get to intelligent life and some of those maybe eventually start
creating simulations, they might get started at quite different times.
Maybe on some planet, it takes a billion years longer before you get monkeys or before you
get even bacteria than on another planet.
This might happen at different cosmological epochs.
Is there a connection here to the doomsday argument and that sampling there?
Yeah, there is a connection in that they both involve an application of anthropic reasoning
that is reasoning about these kind of indexical propositions.
But the assumption you need in the case of the simulation argument is much weaker than
the assumption you need to make the doomsday argument go through.
What is the doomsday argument and maybe you can speak to the anthropic reasoning in more
Yeah, that’s a big and interesting topic in its own right, anthropics, but the doomsday
argument is this really first discovered by Brandon Carter, who was a theoretical physicist
and then developed by philosopher John Leslie.
I think it might have been discovered initially in the 70s or 80s and Leslie wrote this book,
I think in 96.
And there are some other versions as well by Richard Gott, who’s a physicist, but let’s
focus on the Carter Leslie version where it’s an argument that we have systematically underestimated
the probability that humanity will go extinct soon.
Now I should say most people probably think at the end of the day there is something wrong
with this doomsday argument that it doesn’t really hold.
It’s like there’s something wrong with it, but it’s proved hard to say exactly what is
wrong with it and different people have different accounts.
My own view is it seems inconclusive, but I can say what the argument is.
Yeah, that would be good.
So maybe it’s easiest to explain via an analogy to sampling from urns.
So imagine you have two urns in front of you and they have balls in them that have numbers.
The two urns look the same, but inside one there are 10 balls.
Ball number one, two, three, up to ball number 10.
And then in the other urn you have a million balls numbered one to a million and somebody
puts one of these urns in front of you and asks you to guess what’s the chance it’s the
10 ball urn and you say, well, 50, 50, I can’t tell which urn it is.
But then you’re allowed to reach in and pick a ball at random from the urn and that’s suppose
you find that it’s ball number seven.
So that’s strong evidence for the 10 ball hypothesis.
It’s a lot more likely that you would get such a low numbered ball if there are only
10 balls in the urn, like it’s in fact 10% done, right?
Then if there are a million balls, it would be very unlikely you would get number seven.
So you perform a Bayesian update and if your prior was 50, 50 that it was the 10 ball urn,
you become virtually certain after finding the random sample was seven that it’s only
has 10 balls in it.
So in the case of the urns, this is uncontroversial, just elementary probability theory.
The Doomsday Argument says that you should reason in a similar way with respect to different
hypotheses about how many balls there will be in the urn of humanity as it were, how
many humans there will ever have been by the time we go extinct.
So to simplify, let’s suppose we only consider two hypotheses, either maybe 200 billion humans
in total or 200 trillion humans in total.
You could fill in more hypotheses, but it doesn’t change the principle here.
So it’s easiest to see if we just consider these two.
So you start with some prior based on ordinary empirical ideas about threats to civilization
and so forth.
And maybe you say it’s a 5% chance that we will go extinct by the time there will have
been 200 billion only, you’re kind of optimistic, let’s say, you think probably we’ll make it
through, colonize the universe.
But then, according to this Doomsday Argument, you should take off your own birth rank as
a random sample.
So your birth rank is your sequence in the position of all humans that have ever existed.
It turns out you’re about a human number of 100 billion, you know, give or take.
That’s like, roughly how many people have been born before you.
That’s fascinating, because I probably, we each have a number.
We would each have a number in this, I mean, obviously, the exact number would depend on
where you started counting, like which ancestors was human enough to count as human.
But those are not really important, there are relatively few of them.
So yeah, so you’re roughly 100 billion.
Now, if they’re only going to be 200 billion in total, that’s a perfectly unremarkable
You’re somewhere in the middle, right?
It’s a run of the mill human, completely unsurprising.
Now, if they’re going to be 200 trillion, you would be remarkably early, like what are
the chances out of these 200 trillion human that you should be human number 100 billion?
That seems it would have a much lower conditional probability.
And so analogously to how in the urn case, you thought after finding this low numbered
random sample, you update it in favor of the urn having few balls.
Similarly, in this case, you should update in favor of the human species having a lower
total number of members that is doomed soon.
You said doomed soon?
Well, that would be the hypothesis in this case that it will end 100 billion.
I just like that term for that hypothesis.
So what it kind of crucially relies on, the Doomsday Argument, is the idea that you should
reason as if you were a random sample from the set of all humans that will have existed.
If you have that assumption, then I think the rest kind of follows.
The question then is, why should you make that assumption?
In fact, you know you’re 100 billion, so where do you get this prior?
And then there is like a literature on that with different ways of supporting that assumption.
That’s just one example of anthropic reasoning, right?
That seems to be kind of convenient when you think about humanity, when you think about
sort of even like existential threats and so on, as it seems that quite naturally that
you should assume that you’re just an average case.
Yeah, that you’re kind of a typical randomly sample.
Now, in the case of the Doomsday Argument, it seems to lead to what intuitively we think
is the wrong conclusion, or at least many people have this reaction that there’s got
to be something fishy about this argument.
Because from very, very weak premises, it gets this very striking implication that we
have almost no chance of reaching size 200 trillion humans in the future.
And how could we possibly get there just by reflecting on when we were born?
It seems you would need sophisticated arguments about the impossibility of space colonization,
So one might be tempted to reject this key assumption, I call it the self sampling assumption,
the idea that you should reason as if you’re a random sample from all observers or in your
some reference class.
However, it turns out that in other domains, it looks like we need something like this
self sampling assumption to make sense of bona fide scientific inferences.
In contemporary cosmology, for example, you have these multiverse theories.
And according to a lot of those, all possible human observations are made.
So if you have a sufficiently large universe, you will have a lot of people observing all
kinds of different things.
So if you have two competing theories, say about the value of some constant, it could
be true according to both of these theories that there will be some observers observing
the value that corresponds to the other theory, because there will be some observers that
have hallucinations, so there’s a local fluctuation or a statistically anomalous measurement,
these things will happen.
And if enough observers make enough different observations, there will be some that sort
of by chance make these different ones.
And so what we would want to say is, well, many more observers, a larger proportion of
the observers will observe as it were the true value.
And a few will observe the wrong value.
If we think of ourselves as a random sample, we should expect with a probability to observe
the true value and that will then allow us to conclude that the evidence we actually
have is evidence for the theories we think are supported.
It kind of then is a way of making sense of these inferences that clearly seem correct,
that we can make various observations and infer what the temperature of the cosmic background
is and the fine structure constant and all of this.
But it seems that without rolling in some assumption similar to the self sampling assumption,
this inference just doesn’t go through.
And there are other examples.
So there are these scientific contexts where it looks like this kind of anthropic reasoning
is needed and makes perfect sense.
And yet, in the case of the Dupest argument, it has this weird consequence and people might
think there’s something wrong with it there.
So there’s then this project that would consist in trying to figure out what are the legitimate
ways of reasoning about these indexical facts when observer selection effects are in play.
In other words, developing a theory of anthropics.
And there are different views of looking at that and it’s a difficult methodological area.
But to tie it back to the simulation argument, the key assumption there, this bland principle
of indifference, is much weaker than the self sampling assumption.
So if you think about, in the case of the Dupest argument, it says you should reason
as if you are a random sample from all humans that will have lived, even though in fact
you know that you are about number 100 billionth human and you’re alive in the year 2020.
Whereas in the case of the simulation argument, it says that, well, if you actually have no
way of telling which one you are, then you should assign this kind of uniform probability.
Yeah, yeah, your role as the observer in the simulation argument is different, it seems
Like who’s the observer?
I mean, I keep assigning the individual consciousness.
But a lot of observers in the context of the simulation argument, the relevant observers
would be A, the people in original histories, and B, the people in simulations.
So this would be the class of observers that we need, I mean, they’re also maybe the simulators,
but we can set those aside for this.
So the question is, given that class of observers, a small set of original history observers
and a large class of simulated observers, which one should you think is you?
Where are you amongst this set of observers?
I’m maybe having a little bit of trouble wrapping my head around the intricacies of what it
means to be an observer in this, in the different instantiations of the anthropic reasoning
cases that we mentioned.
I mean, does it have to be…
It’s not the observer.
Yeah, I mean, it may be an easier way of putting it is just like, are you simulated, are you
not simulated, given this assumption that these two groups of people exist?
In the simulation case, it seems pretty straightforward.
So the key point is the methodological assumption you need to make to get the simulation argument
to where it wants to go is much weaker and less problematic than the methodological assumption
you need to make to get the doomsday argument to its conclusion.
Maybe the doomsday argument is sound or unsound, but you need to make a much stronger and more
controversial assumption to make it go through.
In the case of the simulation argument, I guess one maybe way intuition pumped to support
this bland principle of indifference is to consider a sequence of different cases where
the fraction of people who are simulated to non simulated approaches one.
So in the limiting case where everybody is simulated, obviously you can deduce with certainty
that you are simulated.
If everybody with your experiences is simulated and you know you’ve got to be one of those,
you don’t need a probability at all, you just kind of logically conclude it, right?
So then as we move from a case where say 90% of everybody is simulated, 99%, 99.9%, it
should seem plausible that the probability you assign should sort of approach one certainty
as the fraction approaches the case where everybody is in a simulation.
You wouldn’t expect that to be a discrete, well, if there’s one non simulated person,
then it’s 50, 50, but if we move that, then it’s 100%, like it should kind of, there are
other arguments as well one can use to support this bland principle of indifference, but
that might be enough to.
But in general, when you start from time equals zero and go into the future, the fraction
of simulated, if it’s possible to create simulated worlds, the fraction of simulated worlds will
go to one.
Well, I mean, it won’t go all the way to one.
In reality, that would be some ratio, although maybe a technologically mature civilization
could run a lot of simulations using a small portion of its resources, it probably wouldn’t
be able to run infinitely many.
I mean, if we take say the observed, the physics in the observed universe, if we assume that
that’s also the physics at the level of the simulators, that would be limits to the amount
of information processing that any one civilization could perform in its future trajectory.
First of all, there’s limited amount of matter you can get your hands off because with a
positive cosmological constant, the universe is accelerating, there’s like a finite sphere
of stuff, even if you traveled with the speed of light that you could ever reach, you have
a finite amount of stuff.
And then if you think there is like a lower limit to the amount of loss you get when you
perform an erasure of a computation, or if you think, for example, just matter gradually
over cosmological timescales, decay, maybe protons decay, other things, and you radiate
out gravitational waves, like there’s all kinds of seemingly unavoidable losses that
Eventually, we’ll have something like a heat death of the universe or a cold death or whatever,
So it’s finite, but of course, we don’t know which, if there’s many ancestral simulations,
we don’t know which level we are.
So there could be, couldn’t there be like an arbitrary number of simulation that spawned
ours, and those had more resources, in terms of physical universe to work with?
Sorry, what do you mean that that could be?
Sort of, okay, so if simulations spawn other simulations, it seems like each new spawn
has fewer resources to work with.
But we don’t know at which step along the way we are at.
Any one observer doesn’t know whether we’re in level 42, or 100, or one, or is that not
matter for the resources?
I mean, it’s true that there would be uncertainty as to, you could have stacked simulations,
and that could then be uncertainty as to which level we are at.
As you remarked also, all the computations performed in a simulation within the simulation
also have to be expanded at the level of the simulation.
So the computer in basement reality where all these simulations with the simulations
with the simulations are taking place, like that computer, ultimately, it’s CPU or whatever
it is, like that has to power this whole tower, right?
So if there is a finite compute power in basement reality, that would impose a limit to how
tall this tower can be.
And if each level kind of imposes a large extra overhead, you might think maybe the
tower would not be very tall, that most people would be low down in the tower.
I love the term basement reality.
Let me ask one of the popularizers, you said there’s many through this, when you look at
sort of the last few years of the simulation hypothesis, just like you said, it comes up
every once in a while, some new community discovers it and so on.
But I would say one of the biggest popularizers of this idea is Elon Musk.
Do you have any kind of intuition about what Elon thinks about when he thinks about simulation?
Why is this of such interest?
Is it all the things we’ve talked about, or is there some special kind of intuition about
simulation that he has?
I mean, you might have a better, I think, I mean, why it’s of interest, I think it’s
like seems pretty obvious why, to the extent that one thinks the argument is credible,
why it would be of interest, it would, if it’s correct, tell us something very important
about the world in one way or the other, whichever of the three alternatives for a simulation
that seems like arguably one of the most fundamental discoveries, right?
Now, interestingly, in the case of someone like Elon, so there’s like the standard arguments
for why you might want to take the simulation hypothesis seriously, the simulation argument,
In the case that if you are actually Elon Musk, let us say, there’s a kind of an additional
reason in that what are the chances you would be Elon Musk?
It seems like maybe there would be more interest in simulating the lives of very unusual and
So if you consider not just simulations where all of human history or the whole of human
civilization are simulated, but also other kinds of simulations, which only include some
subset of people, like in those simulations that only include a subset, it might be more
likely that they would include subsets of people with unusually interesting or consequential
So if you’re Elon Musk, it’s more likely that you’re an inspiration.
Like if you’re Donald Trump, or if you’re Bill Gates, or you’re like, some particularly
like distinctive character, you might think that that, I mean, if you just think of yourself
into the shoes, right, it’s got to be like an extra reason to think that’s kind of.
So on a scale of like farmer in Peru to Elon Musk, the more you get towards the Elon Musk,
the higher the probability.
You’d imagine that would be some extra boost from that.
There’s an extra boost.
So he also asked the question of what he would ask an AGI saying, the question being, what’s
outside the simulation?
Do you think about the answer to this question?
If we are living in a simulation, what is outside the simulation?
So the programmer of the simulation?
Yeah, I mean, I think it connects to the question of what’s inside the simulation in that.
So if you had views about the creators of the simulation, it might help you make predictions
about what kind of simulation it is, what might happen, what happens after the simulation,
if there is some after, but also like the kind of setup.
So these two questions would be quite closely intertwined.
But do you think it would be very surprising to like, is the stuff inside the simulation,
is it possible for it to be fundamentally different than the stuff outside?
Like, another way to put it, can the creatures inside the simulation be smart enough to even
understand or have the cognitive capabilities or any kind of information processing capabilities
enough to understand the mechanism that created them?
They might understand some aspects of it.
I mean, it’s a level of, it’s kind of, there are levels of explanation, like degrees to
which you can understand.
So does your dog understand what it is to be human?
Well, it’s got some idea, like humans are these physical objects that move around and
And a normal human would have a deeper understanding of what it is to be a human.
And maybe some very experienced psychologist or great novelist might understand a little
bit more about what it is to be human.
And maybe superintelligence could see right through your soul.
So similarly, I do think that we are quite limited in our ability to understand all of
the relevant aspects of the larger context that we exist in.
But there might be hope for some.
I think we understand some aspects of it.
But you know, how much good is that?
If there’s like one key aspect that changes the significance of all the other aspects.
So we understand maybe seven out of 10 key insights that you need.
But the answer actually, like varies completely depending on what like number eight, nine
and 10 insight is.
It’s like whether you want to suppose that the big task were to guess whether a certain
number was odd or even, like a 10 digit number.
And if it’s even, the best thing for you to do in life is to go north.
And if it’s odd, the best thing for you is to go south.
Now we are in a situation where maybe through our science and philosophy, we figured out
what the first seven digits are.
So we have a lot of information, right?
Most of it we figured out.
But we are clueless about what the last three digits are.
So we are still completely clueless about whether the number is odd or even and therefore
whether we should go north or go south.
I feel that’s an analogy, but I feel we’re somewhat in that predicament.
We know a lot about the universe.
We’ve come maybe more than half of the way there to kind of fully understanding it.
But the parts we’re missing are plausibly ones that could completely change the overall
upshot of the thing and including change our overall view about what the scheme of priorities
should be or which strategic direction would make sense to pursue.
I think your analogy of us being the dog trying to understand human beings is an entertaining
one, and probably correct.
The closer the understanding tends from the dog’s viewpoint to us human psychologist viewpoint,
the steps along the way there will have completely transformative ideas of what it means to be
So the dog has a very shallow understanding.
It’s interesting to think that, to analogize that a dog’s understanding of a human being
is the same as our current understanding of the fundamental laws of physics in the universe.
We spent an hour and 40 minutes talking about the simulation.
I like it.
Let’s talk about super intelligence.
At least for a little bit.
And let’s start at the basics.
What to you is intelligence?
I tend not to get too stuck with the definitional question.
I mean, the common sense to understand, like the ability to solve complex problems, to
learn from experience, to plan, to reason, some combination of things like that.
Is consciousness mixed up into that or no?
Is consciousness mixed up into that?
Well, I think it could be fairly intelligent at least without being conscious probably.
So then what is super intelligence?
That would be like something that was much more, had much more general cognitive capacity
than we humans have.
So if we talk about general super intelligence, it would be much faster learner be able to
reason much better, make plans that are more effective at achieving its goals, say in a
wide range of complex challenging environments.
In terms of as we turn our eye to the idea of sort of existential threats from super
intelligence, do you think super intelligence has to exist in the physical world or can
it be digital only?
Sort of we think of our general intelligence as us humans, as an intelligence that’s associated
with the body, that’s able to interact with the world, that’s able to affect the world
directly with physically.
I mean, digital only is perfectly fine, I think.
I mean, you could, it’s physical in the sense that obviously the computers and the memories
But it’s capability to affect the world sort of.
Could be very strong, even if it has a limited set of actuators, if it can type text on the
screen or something like that, that would be, I think, ample.
So in terms of the concerns of existential threat of AI, how can an AI system that’s
in the digital world have existential risk, sort of, and what are the attack vectors for
a digital system?
Well, I mean, I guess maybe to take one step back, so I should emphasize that I also think
there’s this huge positive potential from machine intelligence, including super intelligence.
And I want to stress that because some of my writing has focused on what can go wrong.
And when I wrote the book Superintelligence, at that point, I felt that there was a kind
of neglect of what would happen if AI succeeds, and in particular, a need to get a more granular
understanding of where the pitfalls are so we can avoid them.
I think that since the book came out in 2014, there has been a much wider recognition of
And a number of research groups are now actually working on developing, say, AI alignment techniques
and so on and so forth.
So yeah, I think now it’s important to make sure we bring back onto the table the upside
And there’s a little bit of a neglect now on the upside, which is, I mean, if you look
at, I was talking to a friend, if you look at the amount of information that is available,
or people talking and people being excited about the positive possibilities of general
intelligence, that’s not, it’s far outnumbered by the negative possibilities in terms of
our public discourse.
It’s hard to measure.
But what are, can you linger on that for a little bit, what are some, to you, possible
big positive impacts of general intelligence?
Well, I mean, super intelligence, because I tend to also want to distinguish these two
different contexts of thinking about AI and AI impacts, the kind of near term and long
term, if you want, both of which I think are legitimate things to think about, and people
should discuss both of them, but they are different and they often get mixed up.
And then, then I get, you get confusion, like, I think you get simultaneously like maybe
an overhyping of the near term and then under hyping of the long term.
And so I think as long as we keep them apart, we can have like, two good conversations,
but or we can mix them together and have one bad conversation.
Can you clarify just the two things we were talking about, the near term and the long
And what are the distinctions?
Well, it’s a, it’s a blurry distinction.
But say the things I wrote about in this book, super intelligence, long term, things people
are worrying about today with, I don’t know, algorithmic discrimination, or even things,
self driving cars and drones and stuff, more near term.
And then of course, you could imagine some medium term where they kind of overlap and
they one evolves into the other.
But at any rate, I think both, yeah, the issues look kind of somewhat different depending
on which of these contexts.
So I think, I think it’d be nice if we can talk about the long term and think about a
positive impact or a better world because of the existence of the long term super intelligence.
Do you have views of such a world?
I mean, I guess it’s a little hard to articulate because it seems obvious that the world has
a lot of problems as it currently stands.
And it’s hard to think of any one of those, which it wouldn’t be useful to have like a
friendly aligned super intelligence working on.
So from health to the economic system to be able to sort of improve the investment and
trade and foreign policy decisions, all that kind of stuff.
All that kind of stuff and a lot more.
I mean, what’s the killer app?
Well, I don’t think there is one.
I think AI, especially artificial general intelligence is really the ultimate general
So it’s not that there is this one problem, this one area where it will have a big impact.
But if and when it succeeds, it will really apply across the board in all fields where
human creativity and intelligence and problem solving is useful, which is pretty much all
The thing that it would do is give us a lot more control over nature.
It wouldn’t automatically solve the problems that arise from conflict between humans, fundamentally
Some subset of those might go away if you just had more resources and cooler tech.
But some subset would require coordination that is not automatically achieved just by
having more technological capability.
But anything that’s not of that sort, I think you just get an enormous boost with this kind
of cognitive technology once it goes all the way.
Now, again, that doesn’t mean I’m thinking, oh, people don’t recognize what’s possible
with current technology and like sometimes things get overhyped.
But I mean, those are perfectly consistent views to hold.
The ultimate potential being enormous.
And then it’s a very different question of how far are we from that or what can we do
with near term technology?
So what’s your intuition about the idea of intelligence explosion?
So there’s this, you know, when you start to think about that leap from the near term
to the long term, the natural inclination, like for me, sort of building machine learning
systems today, it seems like it’s a lot of work to get the general intelligence, but
there’s some intuition of exponential growth of exponential improvement of intelligence
Can you maybe try to elucidate, try to talk about what’s your intuition about the possibility
of an intelligence explosion, that it won’t be this gradual slow process, there might
be a phase shift?
Yeah, I think it’s, we don’t know how explosive it will be.
I think for what it’s worth, it seems fairly likely to me that at some point, there will
be some intelligence explosion, like some period of time, where progress in AI becomes
extremely rapid, roughly, roughly in the area where you might say it’s kind of humanish
equivalent in core cognitive faculties, that the concept of human equivalent starts to
break down when you look too closely at it.
And just how explosive does something have to be for it to be called an intelligence
Like, does it have to be like overnight, literally, or a few years?
But overall, I guess, if you plotted the opinions of different people in the world, I guess
that would be somewhat more probability towards the intelligence explosion scenario than probably
the average, you know, AI researcher, I guess.
So and then the other part of the intelligence explosion, or just forget explosion, just
progress is once you achieve that gray area of human level intelligence, is it obvious
to you that we should be able to proceed beyond it to get to super intelligence?
Yeah, that seems, I mean, as much as any of these things can be obvious, given we’ve never
had one, people have different views, smart people have different views, it’s like some
degree of uncertainty that always remains for any big, futuristic, philosophical grand
question that just we realize humans are fallible, especially about these things.
But it does seem, as far as I’m judging things based on my own impressions, that it seems
very unlikely that that would be a ceiling at or near human cognitive capacity.
And that’s such a, I don’t know, that’s such a special moment, it’s both terrifying and
exciting to create a system that’s beyond our intelligence.
So maybe you can step back and say, like, how does that possibility make you feel that
we can create something, it feels like there’s a line beyond which it steps, it’ll be able
to outsmart you.
And therefore, it feels like a step where we lose control.
Well, I don’t think the latter follows that is you could imagine.
And in fact, this is what a number of people are working towards making sure that we could
ultimately project higher levels of problem solving ability while still making sure that
they are aligned, like they are in the service of human values.
I mean, so losing control, I think, is not a given that that would happen.
Now you asked how it makes me feel, I mean, to some extent, I’ve lived with this for so
long, since as long as I can remember, being an adult or even a teenager, it seemed to
me obvious that at some point, AI will succeed.
And so I actually misspoke, I didn’t mean control, I meant, because the control problem
is an interesting thing.
And I think the hope is, at least we should be able to maintain control over systems that
are smarter than us.
But we do lose our specialness, it sort of will lose our place as the smartest, coolest
thing on earth.
And there’s an ego involved with that, that humans aren’t very good at dealing with.
I mean, I value my intelligence as a human being.
It seems like a big transformative step to realize there’s something out there that’s
I mean, you don’t see that as such a fundamentally…
I think yes, a lot, I think it would be small, because I mean, I think there are already
a lot of things out there that are, I mean, certainly, if you think the universe is big,
there’s going to be other civilizations that already have super intelligences, or that
just naturally have brains the size of beach balls and are like, completely leaving us
in the dust.
And we haven’t come face to face with them.
We haven’t come face to face.
But I mean, that’s an open question, what would happen in a kind of post human world?
Like how much day to day would these super intelligences be involved in the lives of
I mean, you could imagine some scenario where it would be more like a background thing that
would help protect against some things, but you wouldn’t like that, they wouldn’t be this
intrusive kind of, like making you feel bad by like, making clever jokes on your expert,
like there’s like all sorts of things that maybe in the human context would feel awkward
You don’t want to be the dumbest kid in your class, everybody picks it, like, a lot of
those things, maybe you need to abstract away from, if you’re thinking about this context
where we have infrastructure that is in some sense, beyond any or all humans.
I mean, it’s a little bit like, say, the scientific community as a whole, if you think of that
as a mind, it’s a little bit of a metaphor.
But I mean, obviously, it’s got to be like, way more capacious than any individual.
So in some sense, there is this mind like thing already out there that’s just vastly
more intelligent than any individual is.
And we think, okay, that’s, you just accept that as a fact.
That’s the basic fabric of our existence is there’s super intelligent.
You get used to a lot of, I mean, there’s already Google and Twitter and Facebook, these
recommender systems that are the basic fabric of our, I could see them becoming, I mean,
do you think of the collective intelligence of these systems as already perhaps reaching
super intelligence level?
Well, I mean, so here it comes to the concept of intelligence and the scale and what human
The kind of vagueness and indeterminacy of those concepts starts to dominate how you
would answer that question.
So like, say the Google search engine has a very high capacity of a certain kind, like
retrieving, remembering and retrieving information, particularly like text or images that are,
you have a kind of string, a word string key, obviously superhuman at that, but a vast set
of other things it can’t even do at all.
Not just not do well, but so you have these current AI systems that are superhuman in
some limited domain and then like radically subhuman in all other domains.
Same with a chess, like are just a simple computer that can multiply really large numbers,
So it’s going to have this like one spike of super intelligence and then a kind of a
zero level of capability across all other cognitive fields.
Yeah, I don’t necessarily think the generalness, I mean, I’m not so attached with it, but I
think it’s sort of, it’s a gray area and it’s a feeling, but to me sort of alpha zero is
somehow much more intelligent, much, much more intelligent than Deep Blue.
And to say which domain, you could say, well, these are both just board games, they’re both
just able to play board games, who cares if they’re going to do better or not, but there’s
something about the learning, the self play that makes it, crosses over into that land
of intelligence that doesn’t necessarily need to be general.
In the same way, Google is much closer to Deep Blue currently in terms of its search
engine than it is to sort of the alpha zero.
And the moment it becomes, the moment these recommender systems really become more like
alpha zero, but being able to learn a lot without the constraints of being heavily constrained
by human interaction, that seems like a special moment in time.
I mean, certainly learning ability seems to be an important facet of general intelligence,
that you can take some new domain that you haven’t seen before and you weren’t specifically
pre programmed for, and then figure out what’s going on there and eventually become really
good at it.
So that’s something alpha zero has much more of than Deep Blue had.
And in fact, I mean, systems like alpha zero can learn not just Go, but other, in fact,
probably beat Deep Blue in chess and so forth.
So you do see this as general and it matches the intuition.
We feel it’s more intelligent and it also has more of this general purpose learning
And if we get systems that have even more general purpose learning ability, it might
also trigger an even stronger intuition that they are actually starting to get smart.
So if you were to pick a future, what do you think a utopia looks like with AGI systems?
Sort of, is it the neural link brain computer interface world where we’re kind of really
closely interlinked with AI systems?
Is it possibly where AGI systems replace us completely while maintaining the values and
Is it something like it’s a completely invisible fabric, like you mentioned, a society where
just aids and a lot of stuff that we do like curing diseases and so on.
What is utopia if you get to pick?
Yeah, I mean, it is a good question and a deep and difficult one.
I’m quite interested in it.
I don’t have all the answers yet, but I might never have.
But I think there are some different observations one can make.
One is if this scenario actually did come to pass, it would open up this vast space
of possible modes of being.
On one hand, material and resource constraints would just be like expanded dramatically.
So there would be a lot of a big pie, let’s say.
Also it would enable us to do things, including to ourselves, it would just open up this much
larger design space and option space than we have ever had access to in human history.
I think two things follow from that.
One is that we probably would need to make a fairly fundamental rethink of what ultimately
we value, like think things through more from first principles.
The context would be so different from the familiar that we could have just take what
we’ve always been doing and then like, oh, well, we have this cleaning robot that cleans
the dishes in the sink and a few other small things.
I think we would have to go back to first principles.
So even from the individual level, go back to the first principles of what is the meaning
of life, what is happiness, what is fulfillment.
And then also connected to this large space of resources is that it would be possible.
And I think something we should aim for is to do well by the lights of more than one
That is, we wouldn’t have to choose only one value criterion and say we’re going to do
something that scores really high on the metric of, say, hedonism, and then is like a zero
by other criteria, like kind of wireheaded brain synovat, and it’s like a lot of pleasure,
that’s good, but then like no beauty, no achievement like that.
Or pick it up, I think to some significant, not unlimited sense, but the significant sense,
it would be possible to do very well by many criteria, like maybe you could get like 98%
of the best according to several criteria at the same time, given this great expansion
of the option space.
So have competing value systems, competing criteria, as a sort of forever, just like
our Democrat versus Republican, there seems to be this always multiple parties that are
useful for our progress in society, even though it might seem dysfunctional inside the moment,
but having the multiple value system seems to be beneficial for, I guess, a balance of
So that’s, yeah, not exactly what I have in mind that it, well, although maybe in an indirect
way it is, but that if you had the chance to do something that scored well on several
different metrics, our first instinct should be to do that rather than immediately leap
to the thing, which ones of these value systems are we going to screw over?
Like our first, let’s first try to do very well by all of them.
Then it might be that you can’t get 100% of all and you would have to then like have the
hard conversation about which one will only get 97%.
There you go.
There’s my cynicism that all of existence is always a trade off, but you say, maybe
it’s not such a bad trade off.
Let’s first at least try it.
Well, this would be a distinctive context in which at least some of the constraints
would be removed.
I’ll leave it at that.
So there’s probably still be trade offs in the end.
It’s just that we should first make sure we at least take advantage of this abundance.
So in terms of thinking about this, like, yeah, one should think, I think in this kind
of frame of mind of generosity and inclusiveness to different value systems and see how far
one can get there at first.
And I think one could do something that would be very good according to many different criteria.
We kind of talked about AGI fundamentally transforming the value system of our existence,
the meaning of life.
But today, what do you think is the meaning of life?
The silliest or perhaps the biggest question, what’s the meaning of life?
What’s the meaning of existence?
What gives your life fulfillment, purpose, happiness, meaning?
Yeah, I think these are, I guess, a bunch of different but related questions in there
that one can ask.
I mean, like you could imagine somebody getting a lot of happiness from something that they
didn’t think was meaningful.
Like mindless, like watching reruns of some television series, waiting junk food, like
maybe some people that gives pleasure, but they wouldn’t think it had a lot of meaning.
Whereas, conversely, something that might be quite loaded with meaning might not be
very fun always, like some difficult achievement that really helps a lot of people, maybe requires
self sacrifice and hard work.
So these things can, I think, come apart, which is something to bear in mind also when
if you’re thinking about these utopia questions that you might, to actually start to do some
constructive thinking about that, you might have to isolate and distinguish these different
kinds of things that might be valuable in different ways.
Make sure you can sort of clearly perceive each one of them and then you can think about
how you can combine them.
And just as you said, hopefully come up with a way to maximize all of them together.
Yeah, or at least get, I mean, maximize or get like a very high score on a wide range
of them, even if not literally all.
You can always come up with values that are exactly opposed to one another, right?
But I think for many values, they’re kind of opposed with, if you place them within
a certain dimensionality of your space, like there are shapes that are kind of, you can’t
untangle like in a given dimensionality, but if you start adding dimensions, then it might
in many cases just be that they are easy to pull apart and you could.
So we’ll see how much space there is for that, but I think that there could be a lot in this
context of radical abundance, if ever we get to that.
I don’t think there’s a better way to end it, Nick.
You’ve influenced a huge number of people to work on what could very well be the most
important problems of our time.
So it’s a huge honor.
Thank you so much for talking.
Well, thank you for coming by, Lex.
That was fun.
Thanks for listening to this conversation with Nick Bostrom, and thank you to our presenting
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And now, let me leave you with some words from Nick Bostrom.
Our approach to existential risks cannot be one of trial and error.
There’s no opportunity to learn from errors.
The reactive approach, see what happens, limit damages, and learn from experience is unworkable.
Rather, we must take a proactive approach.
This requires foresight to anticipate new types of threats and a willingness to take
decisive, preventative action and to bear the costs, moral and economic, of such actions.
Thank you for listening, and hope to see you next time.