Grook

A grook (or gruk in Danish) is the name Piet Hein (1905-1996) used for his short, aphoristic poems. They came to wide attention when Martin Gardner mentioned them in his column in Scientific American. Two characteristic grooks:

PROBLEMS

Problems worthy of attack
Prove their worth by hitting back.

OMNISCIENCE

Knowing what
thou knowest not
is in a sense
omniscience.