Saturday, May 31, 2008

Another Way to Prove the Negative

Why don’t you believe in Santa? The Tooth Fairy? Bigfoot? the Loch Ness Monster? Alien visitors? Gefjun the Norwegian Goddess of Agriculture? Sobek, the Egyptian Crocodile God?

It’s frequently charged to the atheist, “you can’t prove a negative,” as if to suggest that under no circumstances is it reasonable to think that something doesn’t exist. But clearly there are a lot of things that you reasonably disbelieve in. And we can say a several things about their similarities and form a principle.

In First Philosophy (1966), Michael Scriven introduced the idea, and then Michael Martin expanded on it in Atheism: A Philosophical Justification. Here’s the idea behind their Santa principle.

In general, you can’t be justified in thinking that some X doesn’t exist unless you have looked. If you haven’t considered the available evidence and reflected on the sources or areas where evidence for the thing’s existence would occur if it was real, then it would be premature to conclude that there isn’t one.

Of course, once you have looked in all the likely places, or explored the relevant concepts, principles, and ideas, if you find evidence in favor of X’s existence, then you should accept that it is real, all other things being equal. So in order to conclude that there is no X the available evidence has to be inadequate in support of it.

But what if the X that we are seeking isn’t the sort of thing that would be manifest by evidence? If it is not the sort of thing that shows itself, then searching in all the right places and then not finding anything wouldn’t be sufficient to justify concluding that it isn’t real.

So the principle that Scriven and Martin give, with a few revisions of my own, is:

A person is justified in believing that X does not exist if all of these conditions are met:

  1. the area where evidence would appear, if there were any, has been comprehensively examined, and
  2. all of the available evidence that X exists is inadequate, and
  3. X is the sort of entity that, if X exists, then it would show.

So for Santa, the Tooth Fairy, aliens, and lots of other cases of reasonable non-existence claims that we believe, these three conditions are met. If there was a Santa, then we’d expect to find some evidence of his existence at the North Pole, in the skies at Christmas, climbing down someone’s chimney, and so on. And we have looked in all the right places where he should be manifest if he is real. But the evidence is inadequate to support the conclusion that he is real. Furthermore, Santa is the sort of being that if he was real, then we’d be able to detect him in some relatively straightforward manner.

The lesson should be clear. Humans have devoted enormous amounts of energy to investigating the God question for millennia. There may be no other thing that we have all spent so much time and effort on trying to find with no results. But by widespread agreement, all of the evidence we have for God’s existence is inadequate to justify the conclusion. Even many prominent philosophical theologians concede the point. And presumably, God, who allegedly wants us to believe in him, and who is involved in the unfolding of events in the real world, would not wish us to labor away in the darkness, not knowing or being able to figure out the most important question ever facing humanity. One would think that he’d need to exert some effort to make his existence as undetectable as it is. It can’t be that he’s not able to make his existence more know to us than it is—if he wasn’t able he’d wouldn’t be worthy of the title.

So it’s reasonable to conclude that God doesn’t exist for the same general reasons that Santa does not. The burden of proof that this creates is that if you think that belief in God is reasonable, then you must either explain how God is importantly distinct from the cases that this principle was derived from, or you must give an argument for thinking that the Santa principle doesn’t apply because there is compelling evidence for God’s existence. Either way you’ve got a very hard task in front of you. It looks like in all the philosophically relevant ways, God is like the non-existing things on our list. Or if you choose to defend the existence of God on the basis of evidence, then you’ve got to produce this bit of reasoning or empirical information that makes belief so clearly agreeable. By widespread agreement, people, including believers, seem to think that belief in God isn’t or cannot be supported by evidence. Even if you think that the existence makes it reasonable to conclude that God exists, no reasonable person thinks that it is obvious or easy to see. So you’ll have the additional burden of explaining why it is that God is making it so hard to detect his existence. And that problem makes it difficult to reconcile the lack of clear evidence with God’s being good, all powerful, and all knowing.


David Fairthorne said...

Actually in mathematics you can and do prove negatives. For instance there exists no rational number whose square is two.

Also in physics, the Michelson Morley experiment used the presumed properties of the luminiferous ether to test for its existence, and the result was negative.

Anonymous said...

I will comment more fully later; I have a lot on my plate right now. But would it be adequate to infer from the sources you referenced and the guidelines you laid out that, back then, Egyptians were in an adequate position to believe in their gods? It seems that justification to reject the existence of X comes iff one has met the guidelines. But they have not met those guidelines. In fact, they have looked, given their level of understanding on the subject, and believed in the Gods. It is only in retrospect that we look back going "Where's the evidence? We have looked and not seen anything, therefore we can justifiably reject your claims you silly Egyptians."

The problem that should be apparent is that the justification either way seems to be relative to the society and the individual, since one individual may have evidence enough for themselves, i.e., "I have looked and seen the Truth!" while everyone else would disagree. How do you reconcile this relativity?

Matt McCormick said...

Good points, Bryan. Yes, to some extent justification is a relative matter. Truth isn't--truth is truth. But someone could be in an epistemic situation where it is completely justified to believe something that is false. Consider the Matrix. Or Ptolemy--he was probably more justified in believing that the Sun orbits the Earth than I am in believing that the Earth orbits the Sun because he had done such a thorough and comprehensive analysis of every bit of information that was available. And two people, like two members of a jury, could be justified in believing opposite conclusions. But of course, the defendant is either innocent or guilty, not both.

As for the Egyptians, I think it is clear that none of them would have been in an epistemic situation where they would have met all four of the conditions in the principle. They were not in possession of the information that many of us are. Of course, there are some people today, home-schooled fundamentalists, for example, who are justified in believing some crazy shit--but mostly because they have had such filtered and tilted access to information.

But let's be clear about the implication of the principle: if the four conditions are met for someone, then they are justified in believing that no such X exists. It does not follow that there are no other ways to be justified in believing it. And it does not follow that no one else can be justified in believing that X exists.

Your suggesting what sounds like a logical error. If P then Q does not imply If ~P then ~Q. Consider: If you are in Sacramento, then you are in California. That's not equivalent to if you are not in Sacramento, then you are not in California. (The first is true, the second false.)

Thanks for the input.


Anonymous said...

So then we do not know if it actually is the case, say, that Santa does not exist under these criteria. We are only justified in believing that Santa does not exist because we believe we have surveyed the relevant landscape, so to speak, enough to conclude that Santa is not on it?

Also, I do not mean to state a logical fallacy. It really depends on the relation between P and Q. I referenced it as an if, and only if. I was unclear as to what extent this relation was symmetric or not (i.e., biconditional). Thanks for clearing that up.

Let me ask you some more questions. If the guidelines are met, one is justified. If the guidelines are not met, one can still be justified, say, by another model of criteria, correct? If the guidelines are not met, one can clearly be unjustified. Now, can one meet the guidelines and still not be justified? In other words, are the guidelines always sufficient to claim justification, across all domains?

My point for bringing that up is that in a simplified logic (e.g., propositional/statement logic), there is no listing of domains or what is being referenced. In short, it inherently has a universal domain analyzing statements. Predicate logic obviously requires domain declaration. The way you have presented these guidelines fits more with the generalized approach with a universal domain. If that is the case, then meeting the guidelines implies justification (P implies Q) universally (given, that it is relative to the informer). Stated alternatively, one model of justification follows from a function (R) of the three criteria (a,b,c). Then any individual obtains the output on a universal input to R(a,b,c). If that is correct, do you understand?

My worry should be obvious that both the universal inputs is questionable (domains should always be considered), and the criteria themselves will admit of specific domains that may not completely mesh (i.e., not all inputs can fall under these guidelines, by design). If that is the case, then the universalized domain conflicts with the specificity in the criteria. An easy work around is to say those things outside of the specific domain will just not obtain an output (like a function outside of some domain simply equals zero, e.g.), but then we still need something to determine the placement of the inputs, i.e., does it fall in or out of the specific meaningful range? With mathematics it is inherent. We know the set from which the numbers belong and how they will behave on a given function. This is not mathematics. In that case, we need an alternative function to determine the inputs placement if there is a conflict; otherwise, if it is not universally applicable in a meaningful manner, then one may come to a false conclusion in which the answer should be "zero" or vice versa.

To simplify that, what is the meta-framework from which this model of justification operates in? I made a comparison to mathematics, which clearly operates in a mathematical framework that has many well-defined parameters and axioms, etc. which allow it all to make sense. If this model does not meaningfully obtain universal inputs, then what framework, what outside of the criteria, will allow us to use them effectively? What framework makes the function, i.e., R(a,b,c), robust?

Rene said...

First may we define our terms. The word Atheism comes literally from the Greek, negative alpha and theos [for God], therefore “negative God” or there is no God. It is not saying, “I do not think or believe there is a God”, rather it affirms the non existence of God. It affirms a negative in the absolute. Anyone who took philosophy 101 knows you cannot affirm a negative in the absolute. It is a logical contradiction. Therefore it is self defeating. It also breaks the rule of non contradiction by ascribing to itself a divine attribute while at the same time denying the existence of the Divine. Atheism not only denounces the existence of God, but by its own definition denounces the principle by which it criticizes the reality of God. To make an absolute statement in the negative is similar to saying that nowhere in the universe does there exist a flying spaghetti monster. For the atheist to make such a claim he must have unlimited knowledge of this universe. What the atheist is fundamentally saying is that he has infinite knowledge of this universe to affirm that there exist no being with infinite knowledge. It is self defeating.
Atheism is a religion and its promoters are its missionaries. Such as Burton Russell who spoke clearly, continually, and with conviction about reality, humanity [what is wrong and what is needed for a better life], and death [where there is no ultimate hope]. Therefore it is a worldview. Since Atheism denies the existence of God it does embrace and defend as sacred any theory that attempts to disprove God. It holds such men as Thomas Hobbes, David Hume, Immanuel Kant, Friedrich Nietzsche, Charles Darwin and many others worthy of their attention and following. And the atrocities of the past two centuries prove that their ideas had consequences.
Now if atheism is true then ultimately there is no moral law in this universe. As a personal philosophy of live it offers no ultimate hope and death is the end of personal existence. Since there is no reference point for the meaning of life there is a complete loss of meaning. And ultimately if the atheist is wrong he has made an unreasonable commitment, for when he dies and finds out that God does exists there is no chance for recovery. But with God you have these and more.
Or are you truly an agnostic who with the evidence, philosophy, and data you have studied, has come to the conclusion that the existence of God cannot be proven with certainty. Agnostic comes from the Greek, alpha the negative and ‘gnosis’ to know, which means “doesn’t know”. That is easy to defend, all you has to prove is that you don’t know.
In God’s perspective there are two types of people those who bend their knee to Him and say “Your will be done”, and those that refuse to bend their knee and say, “No, my will be done.” In the conclusion of things Jesus will honor your choice, either eternal existence with Him, or eternity without Him. Don’t make the mistake of experiencing a Godless eternity because you thought you were too good, for God’s forgiveness, atonement, redemption, and justification.

In His Service

Anonymous said...

TWM: I'm surprised - perhaps unreasonably - to see an apparently rational person resort to Pascal's Wager. Pascal's Wager is an attempt to apply the precautionary principle to life. Better to err on the side of caution. But given the wager's premise that we don't know whether god exists, it follows that we don't know which side the caution lies on.

We don't know which god to believe in. Perhaps you are believing in the wrong one! There are so many to choose from.

We don't know that *belief* is what this god actually values. Perhaps this god rewards people who don't believe without sufficient evidence. Or rewards actions. Or rewards people who have red hair.

Don’t make the mistake of experiencing a Godless eternity because you worshipped the wrong one, or didn't jump through the appropriate hoops.

Anonymous said...

Can you prove there are no fairies? (Let's say a fairy is a spiritual being that is normally invisible but has the capacity to make itself visible to certain people at certain times in the form of a tiny human lady with wings.)

Anonymous said...

What Pascal's Wager is saying is, that they believe their omniscient god is so stupid that he can be fooled by someone pretending to believe "just in case".

It also states that god would favor the pretender over someone who was genuinely moral but did not believe in the unproven existence of any supernatural existence. ''If I were that god, I'd be insulted over that.

I'd also be insulted that I had given my creations intelligence and reason and they chose to throw my gifts away. For some reason, none of this seems to bother theists.