A Literary Quotation

The following more or less explains the title of Joseph Heller's great novel Catch-22, and establishes a principle of circular logic that applies in many more situations than the plight of reluctant bombardier Yossarian. Check it out:

"There was only one catch and that was
Catch-22, which specified that a concern
for one's safety in the face of dangers that
were real and immediate was the process
of a rational mind. Orr was crazy and could
be grounded. All he had to do was ask; and
as soon as he did, he would no longer be crazy
and would have to fly more missions. Orr
would be crazy to fly more missions and
sane if he didn't, but if he was sane he had
to fly them. If he flew them he was crazy
and didn't have to; but if he didn't want to
he was sane and had to. Yossarian was
moved very deeply by the absolute
simplicity of this clause of Catch-22
and let out a respectful whistle."