Thursday, February 16, 2017

The external world and the burden of proof

If both a proposition and its denial cannot be proved, what rules do we use to decide what to believe? If I say "Can you prove that the external world exists" and you can't prove it, should we then not believe that there is an external world?

23 comments:

John Moore said...

It depends on whether a concept is useful for you as you pursue your goals. Believing something just means acting as if you think it's true. Proof doesn't matter as long as you seem to be achieving your goals.

Certainly truth is more likely to be useful than untruth, in the long run, but if you can't figure out for sure what's true, then it makes sense to go with what seems likely and useful.

B. Prokop said...

From FLATLAND by Edwin a> Abbott:

"Look yonder," said my Guide, "in Flatland thou hast lived; of Lineland thou hast received a vision; thou hast soared with me to the heights of Spaceland; now, in order to complete the range of thy experience, I conduct thee downward to the lowest depth of existence, even to the realm of Pointland, the Abyss of No dimensions.

"Behold yon miserable creature. That Point is a Being like ourselves, but confined to the non-dimensional Gulf. He is himself his own World, his own Universe; of any other than himself he can form no conception; he knows not Length, nor Breadth, nor Height, for he has had no experience of them; he has no cognizance even of the number Two; nor has he a thought of Plurality; for he is himself his One and All, being really Nothing. Yet mark his perfect self-contentment, and hence learn his lesson, that to be self-contented is to be vile and ignorant, and that to aspire is better than to be blindly and impotently happy. Now listen."

He ceased; and there arose from the little buzzing creature a tiny, low, monotonous, but distinct tinkling, as from one of your Spaceland phonographs, from which I caught these words, "Infinite beatitude of existence! It is; and there is nothing else beside It."

"What," said I, "does the puny creature mean by 'it'?" "He means himself," said the Sphere: "have you not noticed before now, that babies and babyish people who cannot distinguish themselves from the world, speak of themselves in the Third Person? But hush!"

"It fills all Space," continued the little soliloquizing Creature, "and what It fills, It is. What It thinks, that It utters; and what It utters, that It hears; and It itself is Thinker, Utterer, Hearer, Thought, Word, Audition; it is the One, and yet the All in All. Ah, the happiness, ah, the happiness of Being!"

"Can you not startle the little thing out of its complacency?" said I. "Tell it what it really is, as you told me; reveal to it the narrow limitations of Pointland, and lead it up to something higher." "That is no easy task," said my Master; "try you."

Hereon, raising by voice to the uttermost, I addressed the Point as follows:

"Silence, silence, contemptible Creature. You call yourself the All in All, but you are the Nothing: your so-called Universe is a mere speck in a Line, and a Line is a mere shadow as compared with—" "Hush, hush, you have said enough," interrupted the Sphere, "now listen, and mark the effect of your harangue on the King of Pointland."

The lustre of the Monarch, who beamed more brightly than ever upon hearing my words, shewed clearly that he retained his complacency; and I had hardly ceased when he took up his strain again. "Ah, the joy, ah, the joy of Thought! What can It not achieve by thinking! Its own Thought coming to Itself, suggestive of its disparagement, thereby to enhance Its happiness! Sweet rebellion stirred up to result in triumph! Ah, the divine creative power of the All in One! Ah, the joy, the joy of Being!"

"You see," said my Teacher, "how little your words have done. So far as the Monarch understand them at all, he accepts them as his own—for he cannot conceive of any other except himself—and plumes himself upon the variety of 'Its Thought' as an instance of creative Power. Let us leave this God of Pointland to the ignorant fruition of his omnipresence and omniscience: nothing that you or I can do can rescue him from his self-satisfaction."

B. Prokop said...

By the way, in case I was being too subtle, my "point" behind the quotation from Flatland (one of my favorite SF books) was that, absent an external world, we'd all be like the King of Pointland. Since that is not the case, that all by itself constitutes proof of the existence of something outside of ourselves.

(It's also a good argument for the Doctrine of the Trinity.)

Joe Hinman said...

This is one of the God arguments I make imn my book, using the religious experience studies. This document was meant to show the argumet and why it meets a prima facie justification. In so doing I think it reveals an epistemology that is sort naturally suggested by the argument. The essence of that epistemology is we assume reality is given in experiencing according to the ability of the experience to foster navigation in the world. In short if it works we are justified in assuming it's true.

The argument is bqsed upon those of Thomson Reid. thus is the:

Thomas Reid Argument

This argument in my book The Trace of God but not in the same form.

Joe Hinman said...

In that first link,my argument on Doxa,I think to K.G.Mattey for info on Reid,The Mattey link is real old doesn't work anymore.I don't have one to that exact lecture although there is one in the book, But the Mattey lectures in gneeral be found here:

http://hume.ucdavis.edu/mattey/phi102f03/james.html

The Reid stuff is in there It was originally the Reid project.

Aron Zavaro said...

I think that burdens of proof are closely tied to the concept of prior probabilities. In the absence of any empirical considerations to held us decide between hypotheses, we should favor the ones with higher prior probabilities. Even in the total absence of empirical considerations, some hypotheses can be more probable than others based on factors like simplicity, coherence, modesty, scope, etc.

I think external world realism has a higher prior than skepticism because while realism say that our experiences are real, skepticism posits an additional unevidenced reality on top of our experience, including unspecified agents and requires us to postulate hypothetical intentions and desires on their behalf. This is a more complicated theory than realism.

Victor Reppert said...

But aren't prior probabilities subjective? I have yet to see an objective theory of prior probabilities that, for example, solves the problem of the single case.

Aron Zavaro said...

If priors are subjective, doesn't this entail total epistemological relativism? If you genuinely think that one hypothesis is objectively more likely than another (e.g., it's more likely that the person
writing this post is a human, rather than an alien using mind control technology to manipulate a cat into posting this ), then you must believe that there are objective priors, because posteriors depend on priors. If you think it is objectively true that I am more likely to be a human than a cat, then you should disregard someone who says, "I have assigned a prior of 99.999999% that it was written by a cat, so i think he's really a cat, and you can't say I'm irrational because I'm entitled to whatever priors I want!" That would be irrational. Any commitment to objective knowledge requires that there be some sort of objective grounds for saying that one theory is intrinsically more probable than another. Otherwise, everyone would be entitled to their own "truth."

Joe Hinman said...


sorry Burden pf proof and prior are totally different concept imn my view, they have nothing in common; the former is a formal precept in logic, probability is not logic. BOP is mandated given certain kinds of cloistral but the latter is just a leveraging tool to start miscalculation from. it'snot logic.

Joe Hinman said...

If priors are subjective, doesn't this entail total epistemological relativism?

prior is not proof it's just a coordinated point from which to start calculating. Bayes works like a gunner finding his range. First shooting way over the target doesn't matter where. Then shoots way under. Then he starts playing with the middle between those two points.

B. Prokop said...

Yesterday I ended my 7:17 AM posting with a throwaway line, "[the existence of the external world] is also a good argument for the Doctrine of the Trinity."

Well, since I wrote that, I can't get that thought out of my head. I may have accidentally stumbled onto something here. Creation itself is proof that God is not unitary (e.g., the God of Islam, or of the Unitarians). Were God not in essence a community of Persons, the very idea of anything existing outside of Himself would be impossible even to Him. (Just as, not even God can conceive of a square circle, or a married bachelor.)

So our very existence is proof of not only a Creator, but also of the Doctrine of the Trinity.

William said...

The "problem of the single case" has to do with using a single data point to determine the priors. This is a theoretical problem for frequentists, not Bayesians. The Bayesian is free to use theoretical knowledge to choose a prior that will not be totally influenced by a single case.

Of course, the frequentist in practice will choose a null hypothesis in a way that is not unduly dependent on a single case. The chosen prior of the Bayesian and the chosen hypothesis of the frequentists are in practice analogous.

As Joe says very nicely in the targeting analogy above, the prior is a number needed to start the process of calculation, just so that we have a starting point from which to calculate a more accurate number using the data. Would the target shooter in Joe's analogy deliberately shoot backwards as their first shot at the target? Of course not.

Although the choice of priors may in many cases be subjective in the specific sense that we may not use our own, exact data calculations to choose the prior probability, it may nevertheless be at least partially objective, perhaps based on our experience of the thing we are studying or on numbers given by prior investigator's estimates. "Subjective prior" here may mean "voluntarily picked as a best if overly precise number within the range of our best estimates."

Whereas "total epistemological relativism" would be like blindfolding yourself when shooting just because you are not going to hit the bulls-eye the first shot.

Reconquista Initiative said...

Aron said:

I think that burdens of proof are closely tied to the concept of prior probabilities. In the absence of any empirical considerations to held us decide between hypotheses, we should favor the ones with higher prior probabilities. Even in the total absence of empirical considerations, some hypotheses can be more probable than others based on factors like simplicity, coherence, modesty, scope, etc.

I partially agree, but I think that the burden of proof is actually on the side which puts at greatest risk that which we find most important in a certain setting. That is the real way that the burden of proof is decided, and when it is looked at that way, the burden is on atheism, not theism.

I think external world realism has a higher prior than skepticism because while realism say that our experiences are real, skepticism posits an additional unevidenced reality on top of our experience, including unspecified agents and requires us to postulate hypothetical intentions and desires on their behalf. This is a more complicated theory than realism.

As a Berkelian Immaterialist, this is a pet-peeve of mine. Berkelian immaterialism--or theistic objective virtual realism, if you will--is astronomically simpler than external world realism (naturalism), is as coherent as naturalism, has more explanatory power and scope than naturalism, and is more in line with our indisputable background knowledge than naturalism is, and so on. Thus, if the burden of proof is based on prior probabilities, then the burden is on naturalism / external world realism, not on theistic immaterialism.

Cheers.

Damian Michael
www.reconquistainitiative.com

Victor Reppert said...

I have strong Bayesian inclinations but don't think frequentism or any other objectivist theory of prior probabilities. But a subjectivist account of priors does not lock positions into place, it just acknowledges that different people are going to approach the same data with different perspectives. Strong evidence can "swamp the priors" in many cases. My (quite secular) philosophical education was pretty strongly opposed to classical foundationalism, or the idea that there are certain viewpoints from which everyone has to start. That is why things like the Outsider Test for Faith are very counterintuitive for me, as are de jure "burden of proof" arguments.

William said...

Yes, too often the "burden of proof" arguments and "outsider test" seem to come down to arguments that others change their assumptions or premises (ie priors) without any further evidence that a change of assumptions is needed.

Stardusty Psyche said...

Reconquista Initiative said...

" As a Berkelian Immaterialist, "

Perhaps you sang "Row Your Boat" a few too many times and now you actually believe that life is but a dream.


February 18, 2017 4:15 PM

Stardusty Psyche said...

Victor Reppert said...

" Strong evidence can "swamp the priors" in many cases. "
Evidence indeed.

The burden of proof is on the one making the affirmative claim.

If you assert purple unicorns the burden is on you. I see no purple unicorns, you cannot provide credible evidence for them, so my conclusion that they do not exist is reasonable because you have not even begun to meet your burden for your claim.

"That is why things like the Outsider Test for Faith are very counterintuitive for me,"
Perhaps you would benefit from considering a cult. Inside the cult it all seems so real, David Koresh is the lamb of god, Jim Jones knows the evil ones are coming, The aliens really are passing nearby on a comet. None of these things pass the outsider test.

Consider Islam. To its ardent practitioners Muhammad was the exemplary man, so of course it is good to marry 4 women as young as 9, capture slaves in battles of conquest, slaughter those who resist or defame Islam in any way, extort non Muslims in the kingdom and hold them as second class citizens. It all makes sense to those in the cult, but these things do not pass the outsider test.

Nor does Christianity, or more generally, theism.


February 18, 2017 6:56 PM

B. Prokop said...

"but these things do not pass the outsider test. Nor does Christianity."

Really? Then how do you explain the literally billions of converts (a.k.a. "outsiders") to Christianity over the past two millennia? Seems like a passing grade to me.

Stardusty Psyche said...

B. Prokop said...

"but these things do not pass the outsider test. Nor does Christianity."

" Really? Then how do you explain the literally billions of converts (a.k.a. "outsiders") to Christianity over the past two millennia? Seems like a passing grade to me."
They were successfully indoctrinated into the cult. Cults recruit from the outside, often very successfully. An outsider for the purpose of an outsider test needs to be somebody not susceptible to the indoctrinations techniques of the cult.


February 19, 2017 8:35 PM

B. Prokop said...

"An outsider for the purpose of an outsider test needs to be somebody not susceptible to the indoctrinations techniques of the cult."

You know what they call such techniques in Real Science? FRAUDULENT RESEARCH. That's the type of selective data mining that gets papers rejected from peer review journals and dishonest researchers anathematized by honest scientists.

bmiller said...

@Strawdusty,


"The burden of proof is on the one making the affirmative claim."

This looks like an affirmative claim to me. Please provide the proof that one is obligated to accept the "burden of proof" just by making an affirmative claim, while the opponent is not.

Stardusty Psyche said...

bmiller said...

"The burden of proof is on the one making the affirmative claim."

" This looks like an affirmative claim to me."
Obviously.

" Please provide the proof that one is obligated to accept the "burden of proof" just by making an affirmative claim, while the opponent is not."
You will find it here, February 19, 2017 6:13 PM, right after the claim.

That wasn't so hard, now was it?


February 19, 2017 9:36 PM

Joe Hinman said...

my answer to Eric Sotnak's attack on ID on Secular outpost

HERE