Tuesday, June 24, 2008

Reductio ad absurdum

Reductio ad absurdum, Lat. : Reduction to the absurd

The classic proof by contradiction. The following proves that the universe may not exist.
Caution: Not for the weak-minded.



A thought experiment:


Let the universe exist, and let us exist in it.


  • Consider two human beings : specimen 'A' , that can distinguish between colours the way "normal" humans are expected to, and specimen 'B' who, from birth, sees only in shades of "grey", but can nevertheless, differentiate between colours from the shade of "grey" that he perceives. Note that B does not know what colour would look like to A, and has no way of finding out without swapping memories, and thus assumes that A sees as he does. Vice- versa. Now, present each of them with a colour, say "blue", and ask them what colour it is. Each will say blue, despite the fact that their perceptions are completely different!(If you don't follow, start with a human being and a talking dog.)
  • Extending this to beings in general, it is possible, that each of us would see the colour blue differently, but would still call it blue. That being said, it is possible that the universe looks different to each of us, just that when we describe it in a common language, descriptions by different people may be coherent despite a possible incoherence in perception.
  • Let me take the same argument and push it over the boundaries of colour, and into those of sight in general. And then to the other four senses. Therefore, the universe might be perceived differently by different observers.
  • Now, let us go back to the assumption that the universe exists and we live in it. Being inhabitants of the same universe, we must all receive the same stimuli. And since there can be an infinitely large number of observers, there can thus be infinitely large number of perceptions. (One for each observer at the least.)
  • Now, we have an event( the existence of the universe), and an infinite number of possible observations (an infinite number of observers with as many distinct perceptions of the universe). Basic probability kicks in: the probability of any one observation being true is zero, and since there are infinite possible disinct observations, none of them are true. This leads us to the conclusion that the event may never happen, the event in this case being the existence of the universe. ( I use the word "may" because the argument pivots on whether different observers have different perceptions.)
We can now make the statement : It is possible that the universe does not exist,which contradicts our initial assumption. Hence, our assumption must be incorrect.

Reductio ad absurdum, Lat :Reduction to the absurd

Hence, there is a finite probability that the universe does not exist. (And neither do we!).

Quad erad demonstratum.




42 comments:

Half-Light said...

Arbitax!! Dude Chubzer 2.0 only :)

Bhargav said...

It's brilliantly elegant

Unknown said...

@half... HEY! WHAT AN INSULT! NOTE THE WARNING AND STAY AWAY RATHER THAN COMPARING IT TO LAXATIVE!

Anyway, this reminds me of the discussion we had about this in one of our nocturnal endeavours to find mental peace. However, I have to say that I argue differently, but invariably have to merge with the conclusion.

You see there are infinite perceptions you say. But take the same stimulus and expose two specimens to it. Leave out colour and sight. Take touch for example. When burnt, every human's skin gets burnt to the same degree if all given conditions are similar. So, since all our skins are same for all practical purposes, the response is the same as well. Same goes for any other form of pain, pleasure and what not. We are all equipped with approximately the same quality of instruments to asses these feelings. Since the organs (even cones and rods for that matter), are the same, and the stimulus is the same as well, on the same lines as mathematical induction, and with the power bestowed upon me by occam's razor, I pronounce humans see alike. My green is your green as well, much more probably than not.

What does differ is how our brain chooses to respond to that stimulus which is what makes us different. Which is why I may not like maggi noodles with curd. AheM!

Bhargav said...

@anupam,

What you say makes sense, but its based on the assumption that human beings are alike.
And i say assumption because you can never prove that what i perceive is the same( or different) as what you perceive.

All I'm saying is that I'm open to the idea that there is a possibility( small as it might be) that each organism has a completely different perception.

(And about the skin burning thing, pain is perception too, so one cannot say for sure that it's the same for everyone without assuming that everyone is the same!)

Unknown said...

As I said, I have to agree with your conclusion that it is possible, though highly improbable, which is as far as occam's razor can get us. If our organs are made of the same stuff (of which there is little doubt), I am tempted to make the assumption that they percieve alike as well.

Maybe cyborg research holds the key to this theory. With that in place, we can percieve what another person thinks.

Bhargav said...

True true

Layfield said...

choot. i had discussed this with u i think...not the universe part. the color part.

now for errors:
"One for each observer at the least."
at most

"infinitely large number of observers,"
Considering the universe is finite, no idea how you got this

"the probability of any one observation being true is zero"
????????

"This leads us to the conclusion that the event may never happen"
Oohh, yes especially since everyone just HAS to perceive the universe in a TRUE way just to make the universe real. The existence of the universe is TIED to this fact!!

Bhargav said...

At least. How do you know there aren't lifeforms that cannot percieve the universe in more than one way????

Show me proof that the universe is finte.

Your third comment makes no sense to me. Hail layfield.

Vikram said...

One question: What in the universe may be perceived differently? The way we see/hear/smell/taste/feel it?
This is NOT how the universe is defined. The universe is defined in terms of PHYSICAL LAWS. These are the assumed to be the same for everyone, everywhere. (NO evidence of a contradiction has been found) The speed of light here or on Mars or in the middle of the galaxy will be the SAME who ever measures it by whatever means. A universe is DEFINED by these constants and laws. What you and I perceive as blue is irrelevant.

Layfield said...

"Show me proof that the universe is finte."
well show me the proff the universe is infinite. that argument goes both ways. Lately there has been some evidence that the universe is finite. that soccer ball theory thing.

"the probability of any one observation being true is zero"
why is the probability 0??? and u've shifted from perception and description to observation!! assuming observation refers to the perception. ur saying that the perception is not true. further, the perception not being true has nothing to do with the existence of the universe. because the universe will exist whether or not an observer perceives it correctly. universe cares not for such trivial things.

Bhargav said...

@layfield

Schrodinger begs to differ.

Bhargav said...

@Gulati

Wavelength(colour)is a law. But what you see may not be what I see or what anyone else might see. I have just extended that to perception in general. If there can be an immesurable number of ways to peceive a universe, there is a chance that there is nothing to percieve.

Physical laws can be demonstated/observed only via perception, which as I have argued, need not be common to different perceivers.

Layfield said...

"Schrodinger begs to differ."
okay u either follow 1930 physics or 2000 physics.

and besides, u have no answer for the second point of my second comment.

Bhargav said...

Schrodinger awakes from his grave at layfield's remarks.

Layfield said...

Isn't the sun out in austria right now? Evader.

Vikram said...

Wavelength is NO law. It's just a "quantity" associated with a packet of photons. It is neither constant nor fundamental. The speed of those photons IS a law/constant. A dog measuring the speed of light will find the same answer as an elephant or any other living being. That can tell you that perception goes right out the window as far as "facts" are concerned.

Vikram said...

The entire argument rests on what you've defined as "existence". I don't believe that the universe is a myth just because we see things differently.

Bhargav said...

@Gulati

All of science is based on perception. We can see in 2 dimensions, perceive in 3.

What if there are creatures that can perceive in 20000?

The basics of law establishment is experiment, and the basics of an experiment is observation.. it all boils down to how we perceive things.

Bhargav said...

And I don't believe in the non-existance of the universe either, I find it absurd, I'm open to the possibility, all the same.

Layfield said...

"All of science is based on perception."
No all of science is based on descriptions. So long as all the different perceptions lead to a same description, we don't give a fuck. It's abstracted. let anyone process it however they like. Science still describes the universe and the rules still hold. Because it's output that matters, not process. Input is the same. So long as output is same, it does not matter.

Bhargav said...

Why do you assume we are in a position to identify what is real and what is not?
How do you know what you perceive has a physical manifestation?

Vikram said...

OK. Here's the catch. The speed of light is the same in 1,2,3 or 4 dimension space. We can't measure it in higher dimensions but we're pretty sure it WILL BE THE SAME. That's why it's one of the "constants" of nature. BTW, we perceive in 4 dimensions not 3. Time is the 4th dimension that we can "perceive". The laws of physics predict the existence of 11 space-time dimensions. Irrespective of the number of dimensions perceived by hypothetical beings, they WILL measure same constants (and find their value to be the same) and the experience the SAME laws of Physics as in 4D space-time.

Vikram said...

Nice post btw. It's been a while since I got to think of these things.

Dr. Flycatcher said...

Damn nerds. *shakes fist in air*

Bhargav said...

Haha! at cryptic

Prufrockster said...

On why you are a retard:

1.

That the universe may not exist needs no proof; it is a tautology (p\/~p types).

Take a stand, first.

2.

Consider two human beings : specimen 'A' , that can distinguish between colours the way "normal" humans are expected to ...

When you invoke 'normal[cy]', you're assuming that there exists this standard.

Having read your proof fully, I noticed that you have, possibly, included this reference to 'normal[cy]' only for lucidity. May be you could avoid this problem.

3.

Note that B does not know what colour would look like to A, and has no way of finding out without swapping memories, and thus assumes that A sees as he does. Vice- versa.

Balls! What shit!

First you're assuming that memory is sufficient to perceive colours. This may well not be the case. In fact, the way memory is defined, it, certainly, is not. The areas called Visual Cortices in the Frontal Lobes of the brain are supposed to be related to colour identification; not memory, which probably has more to do with the Limbig System. I wonder what made you think memory has colors. Perhaps you refer to memory as the relationship between the color that is seen and the word (or any other referential interpretation) attached to it, which memory clearly is not.

Your conclusion, thought, that A can not identify colors the way B does, and vice versa, is right, for it follows from definition, not from your stupid claim about memory.

4.

One for each observer at the least.

Balls. One for each observer, at most.

5.

Basic probability kicks in: the probability of any one observation being true is zero...

Fuck man, retarded!

Who the fuck told you? Prove your retard-fucking claim. Nah, don't even try. It isn't worth it. You can't prove it.

Let me elucidate.

The infinite observations you are considering may not be exhaustive. That is, there may be an observation not part of your consideration. In this case your argument is insufficient to claim that ALL possible observations are wrong; may be all observations in the set of infinite observations you have considered are (and anyway, your claim is without proof).

Therefore, let us consider all possible observations, rather than just a subset of cardinality infinity. According to your premise, the universe exists. Hence, it is possible to perceive the universe in its true form, if there exists a person who does (tautology). Now, in the set of all possible persons (the criterion of distinction is the difference in perception), this person is sure to exist. Hence, the probability of one of all the possible observations being true is, you fool, 1 and not 0. This, as you can see, is a consequence of the premise that the universe exists and the exhaustive property of the possibilities in consideration.

Summarily, since the universe exists, one in all possible observations about it will be correct.

I can't even understand where you went wrong while you arrived at your fallacy. Bah.

And incidentally, probability is not required where only binary outcomes to ensue. Otherwise, a simple 0-1 scheme will suffice.

6.

... and since there are infinite possible dis[t]inct observations, none of them are true.

What the fuck, retard?!

7.

This leads us to the conclusion that the event may never happen, the event in this case being the existence of the universe.

The outcomes of an event allow you to speak of its existence, not observations, you dull head. That too, only because the event has occurred and has resulted in the supposed outcomes however frequently as reported. If the 'event' that the universe exists has any outcomes, none of which were possible, then I'd agree that what we thought was the 'event' is not one, at all.

8.

I use the word "may" because the argument pivots on whether different observers have different perceptions.

Your arguments pivots, also, on that mass of shit you should probably be carrying in your cranial cavity. No wonder it's all shaky, retard!

This and point 1 go hand in hand.

--

Gentleman, I totally sympathise (and by sympathise I do not evoke any sense of pity) with your stand, because I think I'm as much of a retard as you are. A theorist may call your stand a 'position' and there is, in large probability, some big guy who has this stand. I don't care about your stand, but don't claim that this is the Gospel Truth and that the kind of shit you give for 'proof' is Proof. Get your 'proof' error free, first. It's hard. But, do not appear to be not-weak-minded (or hypocritical, if you will say that you never did say that about yourself). I can sympathise with any kind of fallacy, not with this shitty kind of pseudness.

Drunkenly,
Melanchoholic.

Layfield said...

omg omg omg :O

Amrut said...

@ melancholy

Points 1,2,4 n 8 were totally unnecessary :

1 - No one needs to take a stand. He's merely expressing an idea he had n is trying to give an explanation for it. Maybe his wording was slightly wrong by bringing in the word "proof", but that's really not the point anyway.

2 - Ever wondered why he used the quotation marks?

4 - At least or at most. Does it really matter??

8 - A mere spam.

On the other points :

3 - This is not a discussion about the structure n functioning of the human brain. It is a discussion related ONLY to physics n maths (n maybe a bit of chemistry for the wavelength part). Please make it a point to display your knowledge in biology in some discussion devoted solely for that subject.

5 - The author made a small mistake. It's not basic probability. It's slightly advanced. N the probability part of the argument perfectly makes sense. The probability of any one observation in an infinite set of observations is so small n negligible that it can be considered 0 for all practical purposes. It all depends on the probability distribution of the observations. (Generally what we come across in life is the normal distribution (bell shaped curve)). Please learn up your math properly before just swotting away some argument. And your take on the infinite set of observations not being completely exhaustive is indeed ridiculous. There is no such thing as "My infinite set of observations" and "Your Infinite set of observations". You may merely argue about the infinite set being countably infinite or uncountably infinite. And an explanation about that now would be digressing from the topic. It's pretty obvious to the guy who knows these concepts that the infinite set considered here is countably infinite. And the probability argument perfectly holds.

6 - I agree that that part of the argument is infact fallacious, but there can certainly be better responses than " What the fuck, retard?! ". The fallacy is that even if the probability is 0, it's not necessary that none of the infinite observations is true. This goes hand in hand with my previous paragraph about probability distributions.

7 - Well, I must say that that's one of the correct things you pointed out.

All in all, we all kinda know where the fallacy lies. Just that there's no necessity to be obstinately blunt in a healthy discussion as this.

@Gulati :
I agree with you. When we consider facts, then no one cares about any1's perceptions. And it's real good to think about stuff like space time n multi dimensional spaces.

Bhargav said...

@ Melancholic

I do NOT assume memory is sufficent to perceive colour, and my argument was about perception, not about memory.

When there are infinite observations, they are ALWAYS exhaustive.And probability CAN predict binary outcomes.

7 doesn't make sense.

If you still get get it, don't try, retard.

Prufrockster said...

Amrut,

I know you don't care much for my blogger name, but, well, I do. Before countering your counter points, I'd like to leave apologies for my slovenly behavior (if you like). I was drunk, and I assumed that this is some pseud discussion.

MV counters me by asking me how I could spell as well. Well, it is just that I've trained myself to compose stuff when I'm drunk.

A social disaster that I am, drunk. You can imagine. Sigh.

Hope you guys won't mind this very much.

Now, for the counters:

1.

Gentleman, if one is to prove something, it better be something to prove. The claim, not mine, but the author's, is that he has a conclusion he is about to prove by the classic method he cites.

Now, one must, trivially, of course, check for the verifiability of this claim. Yes? Which is what I did.

Your defense, if you notice, goes on to say things the author doesn't: that he's merely introducing a certain topic of discussion. I beg to differ. Our man claims more.

Again, you must forgive me for my unparliamentary scene.

2.

And this is interesting.

You seem to believe (correct me if I'm wrong) that quoting helps. My point is still more basic. Quoting may well be a literary technique to cite conventional meaning, but the thought that this conventional meaning refers to the real is the problem I wish to raise. No quoting is possible without a reference to real. I hope I'm clear. I can explain better, but I'm worried I have a long way to go defending.

3.

I cited what you call "Biological" reference only to ask the author not to use the word "memory" thus inappropriately. Also there is a point you seem to miss that memory needs to be interpreted, and this is not done by the memory.

If you want Biological jargon to get away, fine. Here's a better analogy. Treat the memory as the hard disk. The problem we speak of is one of the processor, and not of the memory. Even if you get a new hard disk, you'd procure the similar kind of output only.

Further, I did not see anyone saying 'No Biology'. If you think its a bad science (as in, inaccurate, so on), I can always punch Physics, Chemistry and yes, even Math, if you already haven't been at it.

4.

It does.

Clearly, the distribution with infinite number of observations is not the only possible distribution.

For example, all of us could perceive in just one way. Or, half of us in one way, and another in another way, and so on.

5.1

The author made a small mistake. It's not basic probability. It's slightly advanced. N the probability part of the argument perfectly makes sense.

Good laugh.

5.2

Anyway, your claim:

The probability of any one observation in an infinite set of observations is so small n negligible that it can be considered 0 for all practical purposes. It all depends on the probability distribution of the observations. (Generally what we come across in life is the normal distribution (bell shaped curve)).

5.2.1. This assumes that there are infinite different observations against the one true observation. Now you see why my point 4 is valid?

5.2.2. Which mathematical operation are we performing that does not recognise a small probability? Multiplication? If you think that's what it is, why don't you work us out a theory and some equations rather than claim this and that? Why would we need to compare (by some mathematical operation - probably multiplication) the individual probabilities of certain observations being true or not? And even if we do, what is this quantity all of you claim to be going to a zero value? I simply don't understand this probability scheme and how you relate the individual probabilities!

5.2.3. What makes you think that the probability that one observation is true is small? In fact, I claimed that it is 1.

5.2.4. Good that you speak of distributions. Please work out the number of possible distributions you are to consider, first. You're considering just one case.

5.2.5. What is a normal distribution doing here?

5.3.

Please learn up your math properly before just swotting away some argument.

Lol.

Oh, and by the way, counter my Math before you claim it's wrong.

I make only one claim, and I think it is a sound one (for it is trivial :P).

Since the universe exists, one in all possible observations about it will be correct

5.4.

And your take on the infinite set of observations not being completely exhaustive is indeed ridiculous.

No. Here's an exemplary case.

You claim that an infinite set of observations comprises of all observations (if you don't, then your objection to my argument truthfully implies this).

Take a set of infinite observations. Half the set. I have two sets, neither of them with all observations.

5.5

There is no such thing as "My infinite set of observations" and "Your Infinite set of observations".

I don't remember saying this, nor does my slovenly comment.

5.6

You may merely argue about the infinite set being countably infinite 0or uncountably infinite. And an explanation about that now would be digressing from the topic. It's pretty obvious to the guy who knows these concepts that the infinite set considered here is countably infinite.

So what if there is a digression as long as it clarifies? Anyway, whether this concept is around, or not, my charge that ALL observations have not been checked still exists unanswered.

5.7.

And the probability argument perfectly holds.

Now. That the set considered is, oh what did you call it?, countably infinite makes this whole argument healthy is rather unsound. Neither would it be sound to think so on the basis of your critique of my argument that "the infinite set of observations not being completely exhaustive", which incidentally appears to be ridiculous to your intellect.

6.

You are perfectly right. My apologies.

7.

I hope you now know why I was being blunt. Do pardon me. I hope to be part of your healthy discussion, too.

Most apologetically,
Melanchoholic.

Prufrockster said...

Ah, Bhargav,

1.

Note that B does not know what colour would look like to A, and has no way of finding out without swapping memories, and thus assumes that A sees as he does.

Now, I deduced that you see swapping memories as the magic trick.

2.

When there are infinite observations, they are ALWAYS exhaustive.

Wrong.

Consider the real number set [0,1], for example. The cardinality of this set is infinity.

There exist infinite number of reals not covered by this set. For example, 1.111.

3.

And probability CAN predict binary outcomes.

I don't remember disagreeing.

4.

7 doesn't make any sense

Okay, let me try.

Tossing a coin is an event, let us assume.

What is an event - one that has at least one causal outcome. That is, the event causes the outcome.

We can observe a head or a tail as outcomes of the event. This does not prove that the tossing is an event; rather, these outcomes are consequences of that very assumption.

You may even claim that tossing the cause leads to Gay Marriage Legalisation, or some such thing which, I conjecture, would seem unconnected to many. However, the outcome and the event are not causally related.

Hence, we are required to get a closed set of all possible outcomes before computing any probability.

First of all, it is, thus, your job to show us that the 'observations' you speak of are causal outcomes (if possible!).

If tossing a coin had no possible causal outcomes, then it would no longer be an event.

You see the problem in this?

Probability can be computed only for outcomes of events that have been assumed to exist. It can not be used to negate the very existence of the event.

It is similar to performing the classical error of taking A->B for B->A.

5.

What do you mean I didn't get it? I have raised objections which you don't seem to want to value. So anything I say results from my retardation, from my lack of understanding. If this is the way you will look at counters, then, phew, nothing much can be done.

Melanchoholic.

Bhargav said...

@Melancholic,
My argument is thus:

Whatever we claim to know about the universe is ascribed to the observations we make about it.
The universe can be experienced, for lack of a better word, only via observation.Correct?

When an infinite number of observations can be made about the universe(where you seem to agree with me),
and the truthfulness of each observation(made via sight,sound etc.) is also uncertain (A and B both reporting that a colour is blue,even though they might see it diffferenty; u agree i presume),
then isn't it fair to say none of the observations are trustworthy?

And if none of the observations about the universe are credible, then why should the obsrvation that there is something around us(aka the unviverse) be credible?

It could be nothing, being observed as something, by us "higher lifeforms".
How can you verify that an observer that cannot see, feel ,smell, taste or touch,(such as a chair) is not making the right observation about the universe, that there's nothing out there?

Prufrockster said...

Bhargav,

Melancoholic. Like alcoholic. Or workoholic :)

The trouble with your argument is that you believe that truth is what is 'credible'. It needn't be, does it have to? :)

If truth is a matter of consensus, then, well, you have one. The Universe exist. That's a consensus opinion.

Clearly, you don't seem to believe so. That being the case, why do you need 'credibility' in the observations? If you don't believe in the consensus opinion, apply the same rules of logic, and you don't have to believe in the credibility of observations.

You say:

... A and B both reporting that a colour is blue,even though they might see it different[l]y ...

Invoke the infamous point 7, again. That blue is not seen is not sufficient to prove that blue doesn't exists.

Only if you assume blue exists can you speak with certainty about A and B seeing things other than blue.

What I'm saying is. Blue may well exist. This does not entail that blue is to be seen, in its true form.

This is the largest fallacy in your proof. The existence of the universe does not entail it's true perception :).

Even if you prove (which you haven't, and I don't suppose anyone can) that no human perceives the universe in its true form, it can not be used to negate the existence of the universe.

The universe may well be different from what we perceive. Some facts:

1. Einstein seems to have proved that the world is not in 3D (I don't know, I was just told). May be it's just humans who perceive it in 3D.

2. The retina is a 2D thing. How do you think we perceive things in 3D? :)

Oh, and there are many more things. You may be bored.

Bhargav said...

@ Melancholic

"Invoke the infamous point 7, again. That blue is not seen is not sufficient to prove that blue doesn't exists."
The aim was not to prove absolutely, but to bring to light the possiblility of non-existance.

"What I'm saying is. Blue may well exist. This does not entail that blue is to be seen, in its true form."
While you choose to look at the possiblilty of blue existing, I choose to look at the possibility that it does not.
Same goes for the rest of your counter.

Ultimately, we can never confirm if what we see is true, which means there's a fairly decent chance that there is nothing to see.

Vikram said...

OMG. I think you people have left the discussion far behind.

@Amrut:
Thanks.

@Baggy:
Well, not much except I'd argue from a physics perspective. The Laws of Phy. are facts. There is NO perception coming in anyway.
A photon is a photon however you see it.
To remove the irrational nature of perceptions, laws were made.

Bhargav said...

This is going on forever!!!!
[argh!!]
:)

Vikram said...

Well, you started it :)

Prufrockster said...

Bhargav,

It's nice that you say this.

The aim was not to prove absolutely, but to bring to light the possibility of non-exist[e]nce.

But, machan, I kept saying only this: Good conclusion, incoherent reasoning.

See, you got me wrong, completely.

While you choose to look at the possibility of blue existing, I choose to look at the possibility that it does not.
Same goes for the rest of your counter.


I'm not looking at either possibility. I'm only critiquing what you called a proof. I'm not saying I'm of the opposite position as you are; I'm saying you're not justified in coming to the conclusion using the premises and assumptions you've invoked in your proof.

There is another ripe example for me to explain my state. You claim:

Ultimately, we can never confirm if what we see is true, which means there's a fairly decent chance that there is nothing to see.

Can we confirm if what we see is true, I don't know. But this does not lead to the conclusion. And for this, I gave you reasons in both my comments to you.

At the same time, if you're position is that 'there is nothing to see', cool. No problemo.

Hope I make sense :(

P.S: I'm not leaving any more comments on this one :|

Bhargav said...

@Melancholic,

Hahaha!!!
:)

OK, so I misunderstood you. The argument may have been holey, but conclusion was what I was aiming at. :)

Bhargav said...

PS.

This wil probably be one of the last comments on this post, I'm guessing.Didn't think it would go on for so long!! Lol! :)

Prufrockster said...

Tempted.

Was that sarcasm? :(

Bhargav said...

No. Honest! :)