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

No man of science wants merely to know. He acquires knowledge to appease his passion for discovery. He does not discover in order to know, he knows in order to discover.

You cannot be wise without some basis of knowledge, but you may easily acquire knowledge and remain bare of wisdom.

Religion will not regain its old power until it can face change in the same spirit as does science.

An open mind is all very well in its way, but it ought not to be so open that there is no keeping anything in or out of it.

...the only simplicity to be trusted is the simplicity to be found on the far side of complexity.

Algebra reverses the relative importance of the factors in ordinary language.