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Resolved: That the Bostrom Simulation argument is likely correct.

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Voting Style: Open Point System: 7 Point
Started: 10/26/2009 Category: Science
Updated: 7 years ago Status: Voting Period
Viewed: 2,657 times Debate No: 9832
Debate Rounds (4)
Comments (10)
Votes (1)




The Bostrom Simulation Argument means the argument made by Nick Bostrom in the following paper:

Likely means more likely than not, i.e. having a probability of more than 50%.

Correct: True; in this context, accurately reflecting reality.

To recap, Nick Bostrom argues:

"At least one of the following propositions is true: (1) the human species is very likely to go extinct before reaching a "posthuman" stage; (2) any posthuman civilization is extremely unlikely to run a significant number of simulations of their evolutionary history (or variations thereof); (3) we are almost certainly living in a computer simulation." He collapses the first two propositions in the following sentence, "it follows that the belief that there is a significant chance that we will one day become posthumans who run ancestor-simulations is false, unless we are currently living in a simulation."

I also will not detail the evidence that #1 and #2 are plausible. Regarding #1, this is the argument of Bill Joy, in his famous Wired magazine, Why The Future Does not Need Us." Joy, co-founder of Sun Microsystems and co-author of the Java language specification, is no luddite, yet he agrees with Kurzweil that we are reaching a technological inflection point with Genetic, Robotic, Information and Nano-tech ("GRIN") technologies. See also, Martin Rees, who argues that we have a 50/50 chance of escaping this century. See: . , particularly beginning at the 8 minute mark.

The plausibility of proposition #2 is defended by Ray Kurzweil and other "posthumanists". Kurzweil has a great track record in picking technology trends (i.e. he has made a lot of money predicting the correct direction). He invented the first reading machine for the blind, was influential in OCR technology and invented the synthesizer. Said Bill Gates: "Ray Kuzweil is the best person I know at predicting the future of artificial intelligence."

Kurzweil's book, The Singularity is Near, is replete with graphs showing that not only are we in the midst of exponential growth in a variety of technologies but that we are hitting the "knee" of the curve, i.e. that point where the curve will appear to go verticle from our current perspective. Just to be provocative, here is Kurzweil being interviewed by Glen Beck:

See also, Rees at 12:25 min into the youtube clip.

#2 posits that we will be "post human" but will lack any motivation to do ancestor simulations.

#3 flows logically if #1 and #2 are not correct, assuming you believe in the power of exponential growth to create the singularity discussed by Kurzweil et al.

If anyone doubts that we live in a pivot point of history, Carl Sagan said it best:

"This is the first moment in the history of our planet when any species, by its own voluntary actions, has become a danger to itself - as well as to vast numbers of others."

Sagan further wrote that this pivot point in human history could be a common event for intelligent life evolving in the enormity of the universe:

"It might be a familiar progression, transpiring on many worlds - a planet, newly formed, placidly revolves around its star; life slowly forms; a kaleidoscopic procession of creatures evolves; intelligence emerges which, at least up to a point, confers enormous survival value; and then technology is invented. It dawns on them that there are such things as laws of Nature, that these laws can be revealed by experiment, and that knowledge of these laws can be made both to save and to take lives, both on unprecedented scales. Science, they recognize, grants immense powers. In a flash, they create world-altering contrivances. Some planetary civilizations see their way through, place limits on what may and what must not be done, and safely pass through the time of perils. Others, not so lucky or so prudent, perish."

In his 1961 inaugural address, President Kennedy stated, "The world is very different now. For man holds in his mortal hands the power to abolish all forms of human poverty and all forms of human life."

I will not go further since Bostrom's argument is available to see in the link provided; therefore, I can only add my little touches until the negative takes us in a direction.



Hello and thanks to my opponent for setting up this debate which I hope will be an interesting and thought-provoking one for both of us.

My opponent has agreed in the comments section [1] that he will focus on proving that proposition #3 is true, provided I assert that #1 and #2 are false.


I accept his definition of "likely" as "having a probability of more than 50%." but note that this does not determine a percentage requirement for "very likely", "extremely unlikely" or "almost certainly" as appear in the three propositions.

If "likely" = at least 50% then I propose that:

"Very likely" = at least 60%.
"Extremely unlikely"= not more than 0.01%.
"Almost certainly" = at least 99.999%.

"Posthuman" which is a term I've never heard before is not clearly defined by my opponent. As the literal meaning of this would be 'no longer human' I can only assume that this refers to a point where we would have evolved into a different species (ie. would no longer be able to breed fertile offspring with modern day humans [2]).


The false propositions:

#1: "The human species is very likely [at least 60% probability] to go extinct before reaching a "posthuman" stage."

I believe this is false. While I'm willing to accept that there is a reasonable likelihood that we will die out before evolving into a new species, I'm far too much of an optimist to allow such a high probability of us not making it. I would put this no higher than 55%.


#2: "any posthuman civilization is extremely unlikely [not more than 0.01%. probability] to run a significant number of simulations of their evolutionary history (or variations thereof)."

I think this is false too. While I can accept it's pretty unlikely, I think there is a slim but reasonable chance of this occurring. I'd give it at least 0.02 probability.



That's got the first two (most probable) propositions out of the way. As my opponent has clearly agreed to defend the third proposition only, I don't expect these first two points to be refuted or to come up in the rest of the debate.

It is this next and final proposition below that will be the subject of our discussions.


#3: "We are almost certainly [99.999% probability] living in a computer simulation."

On it's own I think that this is quite an extraordinary claim.



I invite my opponent to present some evidence to prove to me that we are almost certainly living in a computer simulation.



[1] -
[2] -

Thank you.
Debate Round No. 1


Since we are discussing the validity of Bostrom's arguments, all definitions should come from Bostrom. Bostrom's original paper defined the "post human stage of civilization" as that stage ". . . where humankind has acquired most of the technological capabilities that one can currently show to be consistent with physical laws and with material and energy constraints." See Section III.

Con stipulates the following as false : (1) the human species is very likely to go extinct before reaching a "posthuman" stage; (2) any posthuman civilization is extremely unlikely to run a significant number of simulations of their evolutionary history (or variations thereof).

Therefore, we must accept as true: (1) the human species will not go extinct before reaching a "posthuman" stage and (2) any posthuman civilization is likely to run a significant number of ancestor simulations.

If you accept that there will be a siginficant number of ancestor simulations, why should we assume we are in the single version of reality which begat all others? Bostrom argues that the number of simulated universes should vastly exceed the number of unsimulated universes. If posthumans can do it once, they can run the simulation many times. Why then, would we assume we happen to be in the organic original version of reality? If you allow for the possibility of stacking, i.e. simulations within simulations, what are the odds that you are at the bottom of the stack?

The short answer is that there is no basis for assuming we are in the "original" universe. If you concede that we will reach posthuman status and that it is likely we will run ancestor simulations, it is virtually certain we are in later iterations.


Thanks to Haezed for his last post in this most confusing of debates.

My opponent has made no clear argumentation of his own, merely providing links to Bostrom's arguments rather than explaining why proposition 3 is logical himself. Bostrom's argument seems to me to be at it's core, a mathematical and probability based one. My opponent should be giving us the numbers, according to our revised definitions of the rather vague probability terms in the three propositions.

My opponent presented us with three lengthy videos in his first round. While these are all fascinating (apart from Glenn Beck's contribution) they make no reference to Bostrom and his simulation theory and provide no evidence or even suggestion that we are currently living in a computer simulation.

My opponent also misrepresents my position:

Pro: "If you concede that we will reach posthuman status and that it is likely we will run ancestor simulations, it is virtually certain we are in later iterations."

As agreed, I have posited that the first two propositions are false but this does not mean we will certainly reach a "posthuman" stage or that "posthumans" will necessarily conduct a large number of ancestor simulations.

As my opponent has not disputed my interpretations of "very likely", "extremely unlikely" or "almost certainly", I can only assume that he accepts them.

Careful reading of my round one will reveal that I have not "concede[d] that we will reach posthuman status". On the contrary I have suggested that it is "likely" (more than 50%) that we will NOT.

Similarly I have not even nearly conceded "that it is likely we will run ancestor simulations." I have placed this probability as slim as 0.02%!

My opponent's attempt to misconstrue my arguments and shift the burden of proof to me, saying that I must prove we are in the "original" universe is entirely baseless.


Remember my opponent needs to prove that we are not just possibly living in a virtual world but that it is a near certainty, with at least 99.999% probability.

I await some solid argumentation from my opponent.

Until then:

Resolution negated.

Debate Round No. 2


Haezed forfeited this round.


Oh, a forfeit. How disappointing.

Hopefully my opponent will be able to post an argument in the final round.
Debate Round No. 3


Haezed forfeited this round.


My opponent has not taken the opportunity to provide a solid argument and as he has not been online for a week it's hard to know if he's lost interest in the site altogether or just in this debate.

I think my opponent's forfeiting and lack of argumentation should concede the debate in my favour but I will briefly attempt to summarise my position using the maths involved.

I accepted a 55% chance that we would not survive long enough to become 'post human', in the interests of easier maths, I'll adjust this to 50%.

Assuming we do become post human, I have posited a 0.02% chance of us developing a significant number of computer based 'ancestor simulations'.

By my calculations this leaves a 0.01% chance of both of these occurring.

I think the chances of such an artificial world having the minute detail and complexities of the world we experience are extremely slim. The variations in sensory experiences such as taste for example or the complex range of emotions we experience would simply not be necessary for an accurate simulation.

If posthumans were to design such unbelievably complex artificial worlds, I see no reason why they would need to do very many. I would say a thousand would perhaps be the maximum.

If there is a 0.01 chance that ours is one of a thousand different worlds, only one of which is the original, then I believe that would still equate only to a mere 10% possibility that we are living in a virtual world (0.01 x 1000 = 10).

My opponent's assertion that there is a 99.999% probability clearly doesn't add up.

Resolution negated.

Due to the forfeits by my opponent, this debate won't show up on the front page. As I can't vote on the site myself, I request any one reading this, to kindly take the time to vote for whoever they think won the debate according to DDO guidelines.

Debate Round No. 4
10 comments have been posted on this debate. Showing 1 through 10 records.
Posted by Chrysippus 7 years ago
All points to con, due to forfeit. Was an interesting debate, until then.
Posted by Haezed 7 years ago
What's the problem WJM? The first time it was scuttled by a troll. I thought Vi_Veri was in, so I edited it a few times but now made it an open topic. *shrug*

Feverish, I would defend #3 as true if you would stipulate to #2 as false. I would still have to prove that #1 is false, i.e. we will likely make it to a posthuman future (the Kurzweil vrs Joy/Rees debate) but you would not dispute that post humans would at some point have an interest in doing an ancestor simulation. You would be free to argue that they would never have that kind of computing power but I wouldn't have to speculate as to the motivations of posthumans.
Posted by feverish 7 years ago
I would happily go Con against just proposition #3.
Posted by wjmelements 7 years ago
Stop doing this topic.
Posted by Haezed 8 years ago
Vi_Veri, how many rounds would you like?
Posted by DLT_is_zen 8 years ago
I agree with "Rezzealaux". Anything can be likely if one is open minded enough.
Posted by RoyLatham 8 years ago
The proposition seems to me to be true, but with #2 the likely outcome, it's not terribly interesting. Futurist predictions seem like good debate subjects in general.
Posted by Rezzealaux 8 years ago
I attack the definition of "likely" and it's game over.
Posted by TheSkeptic 8 years ago
The problem with futurists is that their vision of the future are too narrow and impoverished...but then again those traits are found in many other realms (politicians, theologians, etc. :D).
Posted by Vi_Veri 8 years ago
Waaaaay too many rounds, or I might take this.
1 votes has been placed for this debate.
Vote Placed by Chrysippus 7 years ago
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