Yeah- you're right. Pythagoras' theorem obviously isn't timeless; the fool took time devising the formula!

Pythagoras did not discover the theorem, it's just named after him. He may have been the first to record a proof of it. It's conceivable that the very first peoples to become seriously interested in geometrical calculation would have discovered it as a matter of course. It does meet the definition of timelessness whereas Lisp does not.

As Wikipedia notes: "Mesopotamian, Indian and Chinese mathematicians are all known to have discovered the theorem independently and, in some cases, provide proofs for special cases."

... which is irrelevant. The point posed was that the ephemeral form heralds the so-called 'revolutionary' concepts, and stating that a prolonged delivery of the concepts invalidates their usefulness is the result of an overly literal interpretation of a common phrase.

Usefulness? When did I say Lisp wasn't useful?