Four play

The Sapir-Whorf hypothesis claims that there is a systematic relationship between the language we speak and the way we see the world. A corollary is that the more important something is to a world view, the more words for it there are likely to be in the language in question. In support of this:

The ancient Greeks had four words for love: agape, eros, philia, storge.

And four words for knowledge: gnosis, episteme, nous, techne. (Thanks to Troy Pierce for pointing this out to me, and thereby inspiring this meditation on fourness).

Aristotle knew four kinds of cause: material, formal, efficient, final.

The Inuit have only four words for snow: aput, gana, piqsirpoq, qimuqsuq; not forty, or two thousand, as is sometimes claimed.

Some eminent Cardinals write forewords that upset traditionalists.

Politicians have forty words for "blind panic", all carefully chosen to sound vaguely reassuring.

West Bromwich Albion fans have four hundred words for relegation,
very few of which I am allowed to reproduce here. As I write, they are heroically resisting the apparently inevitable; but history shows that, like an ancient nature god, the Albion are fated repeatedly to sink from sight, be seen no more in the Premier League for a season or two, and then come back to life, only to succumb again in short order. I am proud to count myself as a supporter of a team that so ably symbolises the underlying rhythm of the created order, even if they're not much good at anything else.