Tuesday, August 12, 2008

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.

1 comment:

Tezza2 said...

You wrote:

"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."

Excuse my ignorance please. I am no philosopher. I would much appreciate you pointing out the flaws in my logic.

Doesn't your statement imply that Descartes started from the premise that there was a "He" who was doing the thinking and then concludes from that assumption that this "He" therefore must have a priori existence?

Didn't Descartes employ the same flawed logic that Christians use when they argue that the Bible is the word of God because God states in that same Bible that this book contains 'His Word'? So it must be true. God can't be wrong?

Perhaps Descartes' 'He' was just a mental construct formulated as a direct result of his infant individuation processes that took place as a child arbitrarily differentiates itself from its surroundings.

No matter how powerful it might appear, will a computer ever be constructed with the degree of technological sophistication to be called a 'He' or a 'She'? If such a computer could think like a human being, would that computer be justified in assuming that it existed as an independent entity labeled a 'He' or a 'She' over, above and transcendent of the hardware responsible for the 'thinking' that it perceives itself to be doing?

If not then from what logical argument did Descartes derive the conclusion that led to his initial 'cogito ergo sum' assumption that there was a 'He' who was doing the thinking in his head?

Why cannot there just be 'thinking' without the existence of any 'He' who is doing it?

Tony Parsons makes just this assertion about his reality when he describes his awakening to 'no independent self-hood'. He wrote:

"Suddenly, there seems to be a shift and an impersonal realization that this is already wholeness. The boundless, naked, innocent, free-floating and wonderful simplicity of beingness is already all there is . . . it is extraordinary in its ordinariness and yet it cannot be described."

Is Parsons right? Are we, as so obviously was Descartes, so indoctrinated by our own sense organs into unquestioningly believing in the independent existence of a transcendent self who owns its own thoughts, feelings, mind and body parts with all their very inter and intra-dependent biological processes?

Was Descartes deceived by his own ego's machinations into implicitly believing in a 'He' who was doing the thinking?

Could Descartes have reworded his famous 'cogito ergo sum' statement into the form:
"There exists 'thinking', therefore 'I' am." If so then would this conclusion logically follow, do you think? Would the before mentioned sophisticated 'super computer' be taken seriously in making this same statement on its auditory output device?