Subject: Re: Who's running your business?
From: Ian Lance Taylor <>
Date: 31 May 2000 14:19:57 -0700

   Date: Wed, 31 May 2000 14:36:27 -0400

   Actually the original statement is reasonably accurate, and proof by
   contradiction is not a contradiction.  It is generally much harder to
   prove false statements than it is true ones - whatever proof
   technique you use.  The only common exception is when one so strongly
   expects the answer to be one thing that you are willing to accept a
   "proof" that actually isn't.  Most proof's of God's existence are in
   this category.  So likewise are many demonstrations that one's
   preferred style of politics/government/economics/etc is really The
   Right Way.

I dunno, I think there are several proofs of the existence of God that
are logically flawless.  We today do not believe them because we feel
that their assumptions are incorrect.  But once you step outside the
realms of pure mathematics and logic, there are always assumptions
beneath everything.  Even programming has assumptions, namely the
correctness and general availability of the system on which the
program will run.

For example, consider Berkeley's proof of the existence of God, which
was the source for the old saw about whether a tree falling in the
forest makes a sound.  To brutally summarize his argument to the point
where it makes almost no sense anyhow, he said that a sound without a
hearer is a meaningless concept, but to think that a tree would fall
without a sound defies common sense, therefore there must be a God--
namely the entity or class of entities who hears every tree fall.  You
can quibble with his definition of a sound without a hearer, or his
definition of common sense, but it's not particularly easy to
discredit his proof as such.  And remember, we have just as many
underlying assumptions in life as Berkeley did.  We happen to think
that ours are more correct, but there is no meaningful way for us to
prove that they are, at least not without making other, different,
assumptions (e.g., Occam's Razor, consilience).

(Nobody believed Berkeley even in his own day, but what they did not
believe was not so much his proof of god, but his further claim that
we are, in essence, merely ideas in the mind of God.)