Hume & why you can't prove a thing exists except by experience

To continue discussion of the ontological argument that I have been making through my last three posts, first with Anselem’s original argument, Descartes’ variation and Kant’s and Russel’s critiques. Now, we can talk about David Hume. Hume wrote a dialogue late in his life called thd "Dialogues Concerning Natural Religion" which he didn't publish in his lifetime because he was worried about the repercussions of what in his day would have been a very incendiary and controversial work. The dialogue is between three characters on the answerability of religious questions, most importantly the existence of the Christian God. His conclusion is basically that we can't prove God's existence, but we should believe it anyways. A number of philosophical arguments on the nature and existence of God are presented and are refuted with cogent reasoning. This includes the ontological argument.

The most important argument for us here, is a general argument presented by Cleanthes in Part IX that we can't prove anything exists a priori. That is, we can't prove that something exists without experience, direct or indirect, of the thing itself. He makes the argument briefly, "Nothing is demonstrable, unless the contrary implies a contradiction. Nothing, that is distinctly conceivable, implies a contradiction. Whatever we conceive as existent, we can also conceive as non-existent," therefore, "There is no Being, whose existence is demonstrable." To put it in other words. The only way that we can know that a thing must exist is if it's opposite is impossible because of internal contradictions. An example of something with internal contradictions would be like a round square or a married bachelor. We will leave aside the issue of how to define opposition precisely that I brought up earlier. There is nothing that we could possibly conceive for which we could not conceive it's opposite. We can't really conceive of a married bachelor. And what would it's opposite be? an unmarried husband? Would the opposite of a round square be a square circle? If we can conceive of a thing we can conceive an opposite that is not internally contradictory. Thus, ultimately we can't prove the existence of anything a priori.

There is nothing internally contradictory about an atheistic universe. Hume himself believed in a theistic universe, but could admit that there was nothing internally contradictory about a atheistic universe. To return to Descartes, one of the things that Descartes tried to ultimately do through his Meditations was to sure that one couldn't actually conceive of God as not existing. He failed in this attempt, but I think he too recognized what Hume did. We should also recognize that Descartes' arguments did not try to be entirely a priori. One of Descartes' arguments begins with the observation that he has an idea of an all-perfect God and the other uses the observation that he can't imagine God as not existing. Even Descartes' famous cogito ergo sum, whereby he proves that he exists by observing that he thinks, relies on the important empirical observation that he is thinking. Descartes was a clever little fellow, even though he clearly has some rather untoward assumptions.

Returning to Hume though, we might be a little skeptical about his initial premise that the only way to prove the existence of something outside of experience is by proving that it's opposite entails a contradiction, but I find this to be a fair assumption and am more than willing to accept that the only way to prove that something exists is through experience.

We would think this would end the proofs of God, but it certainly is not the end of it.