"A what?" I hear you ask.

"A grook."

Many years ago I walked into a second hand book shop and came out with a small volume entitled Still more grooks by Piet Hein. It was a gem and, search though I did, I never found any books entitled 'Grooks' or even 'More grooks' that I could add to my collection.

But what is a grook? Well, it is defined on the back cover in dictionary-style:

grook (grewk) n. a short rhyming epigram, usually accompanied by a relevant illustration

and that is exactly what it is! The interesting thing is that over the years, I have never heard of grooks written by anyone but Piet Hein. So who was he?

He was born in Copenhagen in December 1905. Not only was he a poet, Piet Hein was a mathematician and scientist, an engineer and inventor, or, to put it simply, a polymath. Little known outside Denmark, though he wrote in English with equal ease, he also invented the Soma Cube and, with John Nash, created the game of Hex. He died in 1996.
There is a quote in the flyleaf of the book by A.P. Herbert, in which he says:

... the rhymed epigram ... is a most hazardous enterprise. It must have wit, or wisdom - preferably both - compressed into a tiny space, yet [be] perfectly intelligible. Your obscure 'modern' will write no memorable epigrams ... it must have rhyme and it must scan.

Piet Hein has one of those rare and psychologically mysterious minds, possessed by so many great creative scientists such as Einstein and Niels Bohr, a mind going straight to the heart of the problem, seeing all its aspects in a single unity, then finding a solution that is as unexpected as it is beautiful.

It is published here by kind permission of Piet Hein's son, Hugo Piet Hein.