Gentlemen, the most important part of living is not the living but the pondering upon it. And the most important part of experimentation is not doing the experiment but making notes, very accurate quantitative notes — in ink. I am told that a great many clever people feel they can keep notes in their heads. I have often observed with pleasure that such persons do not have heads in which to keep their notes. This is very good, because thus the world never sees their results and science is not encumbered with them.

Arrowsmith (1925)