Recently, on Twitter, I got into a discussion with two users (@LifesPoser and @JoeUnseen) about the existence of God.  As usual, they were crowing about how I need to prove that God exists before they’ll listen to me.

https://twitter.com/#!/LifesPoser/status/89019071726759937

So I responded with links to three YouTube videos from Dr. Roland Nash:

https://twitter.com/#!/tucholskic/status/89187665408299008

First of all, I doubt that these guys watched all of the videos.  The discussion centered around the first video, where Dr. Nash explains that we as humans take for granted a number of propositions that we are unable to prove.  Two such examples are the existence of an external world and the existence of other minds (known as solipsism; and one user even ridiculed my entire argument by saying that when the theist resorts to solipsism, that means he’s beat).

The shallow reasoning in question:

Not correct, not even a little bit.  Just because I’m experiencing the external world, I can’t call that evidence of the existence of the external world.  All such evidence–picking up a crayon off my basement floor, sitting in a chair, talking to my wife–is part of the very thing I’m trying to prove.

Consider trying to prove a murder in court.  We’re trying to prove that the act itself occurred.  We can’t see the act itself, only the evidence produced by the act.  Security footage (not the actual act, mind you, but a recording of it–the actual act happened in the past and is not accessible to us).  A knife with the defendant’s fingerprints on the handle and the victim’s blood on the blade.  Footprints matching the defendant’s shoes in blood fleeing the crime scene.  These things are incidental to the act itself, they exist as a record of the act.

With trying to prove the external world, everything that you can point to is part of the external world, not a record of its existence.  This is akin to my fellow theists saying that the Bible is God’s word because it says so.  You can’t do that; it’s begging the question.

There are equally plausible metaphysical explanations for an outside world.  Look at The Matrix.  You can’t prove that isn’t what’s happening right now.

So, what?

The take away point is that you are rational for believing in the existence of an external world.  Moreover, you are rational for believing that the people you encounter have minds.  And, you are rational for believing that there is a shared experience with that other person when we’re standing in the same room.  We see the same lamp.  We sit together at the same table.

You can’t prove it.  But, you’d be irrational to consider The Matrix scenario.  You’d be locked up if you came to believe that.  That’s how good The Matrix is at detecting and punishing dissent from it.  (Ooops!  Is that Agent Smith knocking at my door?)

So Alvin Plantinga argues that we are rational for believing in the existence of God without having to provide empirical evidence for it.  I’m not proving the existence of God any more than I’m proving the external world.  I’m providing rational reasons for my belief in God.  These I’ve detailed before:

• The existence of something rather than nothing
• Cosmology points to a universe with an absolute beginning, implying a transcendent cause (a cause cannot be part of the resulting effect)
• Harmony of nature (look at the imbalances caused by transplanting non-indigenous species into a new environment or by the unnatural extinction of a member of that biosphere)
• Complex structure of even inorganic matter
• Appearance of design in biology is best explained by actual design
• Existence of absolute morality (human sacrifice is always wrong, even if the Canaanites, Aztecs, and Mayans [among others] thought it was business as usual)
• DNA is a living language, and languages don’t just “come together” one day
• Conscious existence of humans with a free will

Multiple lines of reasoning (not really evidence or proof) coalesce to make the existence of God much more likely than not.  Each of those items by itself makes God very likely, but the cumulative case becomes much, much stronger.  Pretty tough to shake, in my own estimation.

Now, I know it’s fashionable among atheists to say that I bear 100% of the burden of proof since I’m the “prosecution” making the positive claim (“The defendant committed the crime, your honor!”).  But that’s just American imperialism.  Other justice systems make the defendant bear the burden of proof (“I did not commit the crime, your honor!”).  Given all this, I’d say the atheist (at minimum) has at least one burden of proof, though he’s not going to like hearing me say it.

He owes me reasons why non-belief is rational.  Note that I’m not asking him to prove a negative.  I’m asking for what I just gave here–multiple lines of evidence and argument that make the nonexistence of God more likely than not.  Given the usual squawking about theistic burden of proof, I’m not holding my breath for these reasons.