The Logic of Atheism

Chuck Doswell - 15 April 2011

In some essays I’ve made available on the Web, I’ve discussed the nature of “proof” in science.  Atheists frequently make the assertion that it's impossible to "prove" a negative proposition.  For instance, I might postulate a being made up entirely of a plate of spaghetti and meatballs that has created us and the universe.  I’d have to show by some purely logical argument that such a being is in fact impossible.  You can argue, for instance, that no plate of spaghetti and meatballs has ever even shown any sign of being capable of thought, let alone the ability to create a universe.  However, such an argument is empirical rather than logical -- that is, it's based on existing evidence.  There could be a pasta dinner plate somewhere in the universe that’s sentient and in fact is omniscient and omnipotent.  To say that an omniscient, omnipotent pasta dinner is impossible is to claim your own omniscience, at the very least. Unfortunately, no human being can make such a claim legitimately.  This hypothetical pasta dinner being must remain a logical possibility, no matter how absurd it might seem.

Of course, it’s possible to "prove" some sorts of negative statements, provided the standard of "proof" is not absolute.  Suppose I propose that the President of the United States is a being made up of a plate of spaghetti and meatballs.  Given that many of us followed the election of Barack Obama as President of the United States, and we regularly see broadcasts of his news conferences and various Presidential activities, it would be reasonable to consider this an empirical demonstration of the negative:  the President of the United States is pretty evidently not a being made up of a dinner of spaghetti and meatballs.  Unfortunately, common, everyday experience is not even up to the standards of scientific evidence (such experience would be described as anecdotal evidence), so it's quite distant from a purely logical argument capable of providing absolute proof.  Nevertheless, many of us accept our own personal experiences as pretty compelling evidence that the US President is not a being made from a plate of spaghetti and meatballs.

What sort of evidence can we muster for the non-existence of a particular supernatural deity?  Several books have been written to show the "evidence" against the existence of the supernatural beings described in monotheistic religions.  I applaud such efforts, as they constitute a major reason why someone should be skeptical about the deities proposed in the major monotheistic religious cults (Yes, I consider them cults!).  But they always fail to attain that impossibly high bar of absolute proof (of the sort embodied in mathematical, rather than scientific, "proof" standards).  Therefore, the existence of the postulated deity has to remain at least a logical possibility, despite the absence of much in the way of empirical evidence.

But consider the pragmatic, relatively attainable standard of scientific evidence.  The Law of Gravity first proposed by Isaac Newton is an example of how scientific evidence for a hypothesis can be pretty compelling, even if it's not absolute proof.  Suppose you were to dispute the Law of Gravity on purely logical grounds, claiming that it doesn’t work, or whatever.  How confident might you be that you could, for instance, hurl yourself off a precipice into a canyon two hundred meters deep and yet gravity would not operate on you according to Newton's Law of Gravity so as to dash your fragile body on the rocks below?  It’s logically possible using the laws of quantum mechanics to propose you might survive the experience of throwing yourself off a cliff (without a parachute, of course), but it's extremely unlikely!  It’s so unlikely as to render it pragmatically impossible, even if the logical possibility of survival still exists.  I can in all practical matters operate as if I believe in the non-existence of a supernatural deity, even though I also maintain that such a being is still a remote logical possibility.

If you believe in a supernatural deity who blesses you with faith in him/her/it, then perhaps you trust that your deity will intervene on your behalf when you jump off that cliff.  Just how confident are you that your deity will act to prevent your death?  But wait! If that deity were to perform such a "miracle", that would constitute stunning new evidence of his/her/its existence!  Unlike in biblical times, your deity apparently is unable to intervene because he/she/it would give away his/her/its existence (Exactly why is this forbidden now, but wasn’t forbidden in biblical times?  I see no obvious reason for this change of heart on the part of the proposed deity.)!  Too bad for you, though -- despite your unwavering faith, the outcome is almost certainly your demise on the rocks at the base of the precipice.  Masking his/her/its existence apparently trumps saving you, but at least you get to go to heaven and live in eternal bliss in compensation for your faith.  But wait!  Isn't suicide a mortal sin?  Your act of faith could be interpreted as suicidal.  Oops!  Sorry, but you're set to live out the rest of eternity in torment for the sin of killing yourself.  But you’re compensated in your endless agony because you know your deity loves you!! 

Believers might wish to conduct this scientific experiment as a test of their faith.  Are you willing to show us how sincerely you believe in your deity!