In description

I don't think I've ever heard the concept explained any better than this:

'Well you see, Norm, it's like this. A herd of buffalo can only move as fast as
the slowest buffalo. And when the heard is hunted, it is the slowest and weakest ones at the back that are killed first. This natural selection is good for the herd as a whole, because the general speed and health of the whole
group 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. Now, as we know, excessive intake of alcohol kills brain cells. But naturally, it attacks the slowest and weakest brain cells first. In this way, regular consumption of beer eliminates the weaker brain cells, making the
brain a faster and more efficient machine. And that, Norm, is why you always feel smarter after a few beers.’