Kind: captions
Language: en
so part three of the argument says that
so that leads us to a place where
eventually somebody creates a simulation
that I think you 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 well 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
but what you get to if you accept
alternative three first is that would be
more simulated people with our kinds of
experiences and non simulated ones like
if in in kind of if you look at the
world as a whole by the end of time as
it were just count it up that would be
more simulated once than on simulated
ones then there is a 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 this
statement we are probably in a
simulation so here you are introducing
an indexical statement like it's that
this person right now is in a simulation
there are all these other people you
know that are in simulation so some that
are not in the simulation but what
probability should you have that you
yourself is one of the simulated ones
right it's a setup so so yeah so I call
it the bland principle of indifference
which is that in in cases like this when
you have to I guess 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 design a
probability that's proportional to the
size of these sets so that if there are
ten times more simulated people with
your kinds of experiences you would be
ten 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 probabilities yeah kinda
size of the set it seems it seems pretty
plausible to me were the holes in this
is it at the at the very beginning the
assumption that everything stretches
sort of you have infinite time
essentially you don't need infinite time
you should need what how long this is
the time but however long it takes I
guess for a universe to produce an
intelligent civilization that has
intense the technology to run some
ancestry simulations gotcha
at some point when the first simulation
is created that stretch of time just a
little longer than they're all start
creating simulations kind of like yeah
well I mean there might the different it
might 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 intolerant life and some of
those maybe eventually start creating
simulations they might get started at
quite different times like maybe on some
planet it takes a billion years longer
before you get like monkeys or before
you get even bacteria then on another
planet so that like this might happen it
kind of at different cosmological epochs
is there a connection here to the
Doomsday argument in that sampling there
if there is a connection in that they
both involve an application of anthropic
reasoning that is reasoning about these
kind of indexical compositions but the
assumption you need in the case of the
simulation argument it's much weaker
than the simulator the assumption you
need to make the Doomsday argument go
through what is the Doomsday arguing and
maybe you can speak to the anthropic
reasoning in more general yeah that's
that's a big an interesting topic in its
own right and tropics but the Doomsday
argument is this really first discovered
by Brandon Carter it 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 golf is 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
and I can say what the argument is yeah
yeah so maybe it's easiest to explain
via an analogy to sampling from urns so
you imagine you have a big imagine you
have two urns in front of you and they
have balls in them that have numbers so
there's the deterrence looked the same
but inside one there are 10 balls
Paul number 1 2 3 up to ball number 10
and then in the other urn you have a
million balls numbered one to a million
and now somebody puts one of these urns
in front of you and asked you to guess
what what's the chance it's the 10 ball
and you say 50/50 they you know I can't
tell which one it is um 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 7 so
that's strong evidence for the 10 ball
hypothesis like it's a lot more likely
that you would get such a low numbered
ball if they're on the 10 balls in the
urn like it's in fact 10 percent done
right then if there are a million balls
it would be round likely you would get
number 7
so you perform a Bayesian update and
if your prior was 50/50 that it was the
temple earn you become virtually certain
after finding the random sample was
seven that it's only has ten balls in it
so in the case of the urns this is on
controversial just elementary
probability theory the Doomsday argument
says that you should reason in a similar
way with respect to different hypotheses
about how many many balls there will be
in the urn of humanity I said for how
many humans that will have human being
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
will make it through colonize the
universe in but then according to this
Tuesday argument you should think of
your own birth rank as a random sample
so your birth 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 in roughly how
many people have been born before you
that's fascinating because I probably
yeah we each have a number wait wait
wait we would each have a number in this
I mean obviously the exact number will
depend on where you started counting
like which ancestor start was human in
hasta countless human but the does those
are not really important - they're
relatively few of those so yeah so
you're roughly a hundred billion now if
they're only gonna be 200 billion in
total that's a perfectly unremarkable
number you're somewhere in the middle
right just run-of-the-mill human
completely unsurprising yes now if
they're gonna be 200 trillion you would
be remarkably early like you it's like
what are the chances out of these 200
trillion human that you should be human
number one hundred billion that seems it
would have a much lower conditional
probability and so analogously taha in
the urn case you thought after finding
this low numbered random sample you
updated 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 doom soon well you said doom
soon that's yeah well that would be the
hypothesis in this case that it will end
just a hundred billion I just like that
term for the hypothec and of crucially
relies on the Doomsday argument it's the
idea that you should reason as if you
were a random sample from the set of all
humans that will ever have existed if
you have that assumption then I think
the rest kind of follows the question is
why should you make that assumption in
fact you know you're 100 billion so so
where do you get this prior and and then
there is like a literature on that with
different ways of supporting that or
something and that's just one example of
a topic reasoning right there yeah that
seems to be kind of convenient when you
think about humanity when you when you
think about us 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 a 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 can 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 blah blah so what
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 cell
sampling assumption to make sense of
bonafide a scientific inference in
contemporary cosmology for example you
have these multiverse theories and
according to a lot of those all possible
human observations are made so I mean 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
some 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
elucidation so there is a local
fluctuation or an statistically
anomalous measurement these things will
happen and if in us observers make in us
different observations that would be
something 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
very improper bility to observe the true
value and that well then allow us to
conclude that the evidence we actually
have is evidence for the theories we
think are supported it kind of done is a
way of making sense of these inferences
that clearly seem correct that we can
you know make various observations and
infer what the temperature of the cosmic
background is and and the 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 the
examples so so there are these
scientific context so it looks like this
kind of anthropic reasoning is needed
and makes perfect sense and yet in the
case of the dupes argument it has this
weird consequence and people might think
there is something wrong
with it there so there's done this
project that would consistent try to
figure out now 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 anthropic s-- and their
different views of looking at that and
it's a difficult methodological area but
to tie it back to the simulation
argument the the key assumption there
this land principle of indifference it's
much weaker than the self sampling
assumption so if you think about in the
case of the Doomsday argument it says
you should reason as if you're a random
sample from All Humans that would have
lived even though in fact you know that
you are about number 100 billion human
and you're alive in the year 2020
whereas in the case of the simulation
argument all it tested 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 is the observer in the
simulation argument is different it
seems like like who is the observer I
mean I keep assigning the individual
consciousness yeah I mean when I say
yeah when a lot of observers in the
simulation in the context of the
simulation argument but they're all
irrelevant the server's would be a the
people in original histories and be the
people in simulations so this would be
the class of observers that we need I
mean there also may be 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
well observers
I'm maybe having a little bit trouble
wrapping my head a head around the
intricacies of what it means to be an
observer and this and this in the
different instantiations of the
anthropic reasoning cases that we
mentioned I mean it now it I mean it may
be an easier way of putting it is just
like are you simulated or you're not
simulated
you've given this assumption that these
two groups of people exist yeah in the
simulation case it seems pretty
straightforward it's yeah so I think the
key point is the method logical
assumption you need to make to get the
simulation argument to where it wants to
go is much weaker and less problematic
then the methodological assumption you
do make to get the Doomsday argument to
its conclusion may be the dune star
government 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 Doomsday
argument
sorry it's simulation argument I guess
one maybe way intuition pub to like
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 I obviously you can deduce
with certainty that you are simulated
right if everybody with your experiences
is simulated and you know you're got to
be one of those you don't need the
probability at all you just kind of
logically conclude it right right so
then as we move from a case where say
ninety percent of everybody simulated
99% 99.9% it's impossible that the
probability of sine should sort of
approach one certainty as the fraction
approaches the case where everybody is
in a simulation yeah like you wouldn't
like expect that to be a discrete well
if there's one non simulated person then
it's 50/50 but if we move that and it's
hundred percent like it should kind of
all right there are other arguments as
well one can use to support this blind
principle of indifference but that might
be not - 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 simulated worlds will
go to one well I mean it one's a
novelist kind of go all the way to one
in in reality that would be some ratio
although maybe at economical mature
civilization could run a lot of
simulations using a small portion of its
resources it probably wouldn't be able
to run infinite demand yeah 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 right and
there's like well first of all there's
limited amount of matter you can get
your hands off because with the positive
cosmological constant the universe is
accelerating there's like a finite
sphere of stuff even if you've 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 eraser of a
computation or if you think for example
just matter gradually over cosmological
timescales decay you know maybe protons
decay other things and they radiate out
gravitational waves like there's all
kinds of seemingly unavoidable losses
that occur so eventually we'll have
something like like a heat death of the
universe or if it caused death or
whatever but it's finite but of course
we don't know which if if there's many
ancestral civil 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 there's a
physical universe to work with sorry
what I mean that that could be sort of
okay so if simulations spawn other
simulation tries it seems like each new
spawn has fewer resources to work with
yeah
but we don't know at which love which
step along the way we are at right
anyone observer doesn't know whether
we're in level 42 or 100 or 1 or is that
not matter for the resources I mean I
mean it's true that they would that
would be all certainty asked you could
have stacked simulations yes and that
couldn't be a certainty as to which
level we are at as you remark tall so
all the computations performed in a
simulation within the simulation also
have to be expended at the level of the
simulation well today the computer in
basement reality where all these
simulations for the simulations with the
simulations are taking place like that
that computer ultimately it's it's its
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 if 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 lower down in the tower I love
the term basement reality
you