We must not take the faults of our youth with us into old age, for age brings along its own defects.

Not the maker of plans and promises, but rather the one who offers faithful service in small matters. This is the person who is most likely to achieve what is good and lasting.

Live dangerously and you live right.

In all our academies we attempt far too much. ... In earlier times lectures were delivered upon chemistry and botany as branches of medicine, and the medical student learned enough of them. Now, however, chemistry and botany are become sciences of themselves, incapable of comprehension by a hasty survey, and each demanding the study of a whole life, yet we expect the medical student to understand them. He who is prudent, accordingly declines all distracting claims upon his time, and limits himself to a single branch and becomes expert in one thing.

You can put up with everything in this world except not with a long stretch of beautiful days.

Hypotheses are only the pieces of scaffolding which are erected round a building during the course of construction, and which are taken away as soon as the edifice is completed.

Impotent hatred is the most horrible of all emotions; one should hate nobody whom one cannot destroy.