Hay is for Horses... :-) by Freeman Dyson

My suggestion is not original. I don't remember who gave me the idea,

but it was probably Lynn White, with Murray Gell-Mann as intermediary.

The most important invention of the last 2,000 years was hay.

In the classical world of Greece and Rome, and in all earlier times, there was no hay.

Civilization could exist only in warm climates,

where horses could continue to graze through winter.

Without grass in winter, you could not have horses, and without horses

you cannot have urban civilization.

Sometime during the so-called Dark Ages, some unknown genius invented hay;

forests were turned into meadows, hay was reaped and stored. and

civilization moved north over the Alps.

So hay gave birth to Vienna and Paris and London and Berlin,

and later to Moscow and New York.

FREEMAN DYSON is professor of physics at the Institute for Advanced Study

in Princeton, New Jersey. His professional interests are mathematics and astronomy.

Among his many books are Disturbing the Universe, Infinite in All Directions, Imagined Worlds,

and The Sun, the Genome, and the Internet (1999).