"A herd of buffalo can only move as fast as the slowest buffalo. And when the herd is hunted, the slowest and weakest are killed first. This is good for the herd, because the health of the herd keeps improving by the regular killing of the weakest members.
In much the same way, the human brain can only operate as fast as the slowest brain cells.
Excessive intake of alcohol, as we know, kills brain cells. But naturally, it attacks the slowest and weakest cells first.
That's why you always feel smarter after a few beers."
Cliff Clavin from Cheers