There is no more miserable human being than one in whom nothing is habitual but indecision.

Once a decision is reached, stop worrying and start working.

To begin with, our knowledge grows in spots. The spots may be large or small, but the knowledge ever grows all over... What you first gain from them is probably a small amount of new information, a few new definitions, or distinctions, or points of view. But while these special ideas are being added, the rest of your knowledge stands still, and only gradually will you 'line up' your previous opinions with the novelties I am trying to instil, and modify to some slight degree their mass.

When you have broken the reality into concepts you never can reconstruct it in its wholeness.

If an unusual necessity forces us onward, a surprising thing occurs. The fatigue gets worse up to a certain point, when, gradually or suddenly, it passes away and we are fresher than before!

Genius... means little more than the faculty of perceiving in an unhabitual way.

Ninety-nine hundredths or, possibly, nine hundred and ninety-nine thousandths of our activity is purely automatic and habitual, from our rising in the morning to our lying down each night.