Is life worth living? It all depends on the liver.

Psychology is a science, and teaching is an art; and sciences never generate arts directly out of themselves.

All our life, so far as it has definite form, is but a mass of habits.

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!

Time itself comes in drops.

...By far the most usual way of handling phenomena so novel that they would make for a serious rearrangement of our preconceptions is to ignore them altogether, or to abuse those who bear witness for them.

Results should not be too voluntarily aimed at or too busily thought of. They are sure to float up of their own accord from a long enough daily work at a given matter.