Prove What Can’t Be by Not Seeing It

When G. K. Chesterton was arguing against a rationalist who denied miracles on the ground that experience is against it, he cited this:

There was a great Irish Rationalist of this school who, when he was told that a witness had seen him commit a murder, said he could bring a hundred witnesses who had not seen him commit it. (Gilbert Keith Chesterton, 176)

via http://www.desiringgod.org.