(I'm not sure if the following one is a true story or not)
The great logician Bertrand Russell (or was it A.N. Whitehead?)
once claimed that he could prove anything if given that 1+1=1.
So one day, some smarty-pants asked him, "Ok. Prove that
you're the Pope."
He thought for a while and proclaimed, "I am one. The Pope
is one. Therefore, the Pope and I are one."
[NOTE: The following is from merritt@Gendev.slc.paramax.com (Merritt).
The story about 1+1=1 causing ridiculous consequences was, I believe,
originally the product of a conversation at the Trinity High Table.
It is recorded in Sir Harold Jeffreys' Scientific Inference, in a note
to chapter one. Jeffreys remarks that the fact that everything
followed from a single contradiction had been noticed by Aristotle (I
doubt this way of putting it is quite correct, but that is beside the
point). He goes on to say that McTaggart denied the consequence: "if
2+2=5, how can you prove that I am the pope?" Hardy is supposed to
have replied: "if 2+2=5, 4=5; subtract 3; then 1=2; but McTaggart and
the pope are two; therefore McTaggart and the pope are one." When I
consider this story, I am astonished at how much more brilliant some
people are than I (quite independent of the fallacies in the
Since McTaggart, Hardy, Whitehead, and Russell (the last two of whom
were credited with a variant of Hardy's argument in your post) were
all fellows of Trinity and Jeffreys (their exact contemporary) was a
fellow of St. Johns, I suspect that (whatever the truth of Jeffreys'
story) it is very unlikely that Whitehead or Russell had anything to do
with it. The extraordinary point to me about the story is that Hardy
was able to snap this argument out between mouthfuls, so to speak, and
he was not even a logician at all. This is probably why it came in
some people's minds to be attributed to one or other of the famous