The ancient Greeks used it to describe the state of the universe before creation. A sort of hazy, disordered gaseous state. Out of this chaos emerged the cosmos (a beautiful word), which implied the lovely ordered world we see around us, existing according to definite laws and rules. It was the entire universe, with its beauty, grandeur, and interconnectedness. The cosmos was orderly and sensible. Chaos was disorder and nonsense.

Chaos was about as bad as a word could go, and hence there was no way but up. Now chaos is the name of the new science that has revolutionised the way we look at nature. Chaos is a science of everyday things—of art and economics, of biological rhythms and traffic jams—giving new insights into the workings of nature. Not bad for a word with such lowly beginnings. On the other hand, Cosmos had nowhere to go but down. It slowly took on restrictive meanings of beauty and, worse, superficial beauty, and now remains with us in the form of the word "cosmetic". So we see that what was nonsense becomes a science, and what was order and grandeur becomes superficial and silly. An apt description of today's absurd situation.