It is natural to think that an abstract science cannot be of much importance in affairs of human life, because it has omitted from its consideration everything of real interest.

On the ostensible exactitude of certain branches of human knowledge, including mathematics. The exactness is a fake.

Nobody has a right to speak more clearly than he thinks.

Every epoch has its character determined by the way its population reacts to the material events which they encounter.

Education which is not modern share the fate of all organic things which are kept too long.

The study of mathematics is apt to commence in disappointment... We are told that by its aid the stars are weighed and the billions of molecules in a drop of water are counted. Yet, like the ghost of Hamlet's father, this great science eludes the efforts of our mental weapons to grasp it.

A race preserves its vigor so long as it harbors a real contrast between what has been and what may be; and so long as it is nerved by the vigor to adventure beyond the safeties of the past. Without adventure civilization is in full decay.