An unflinching determination to take the whole evidence into account is the only method of preservation against the fluctuating extremes of fashionable opinion.

The pursuit of mathematics is a divine madness of the human spirit.

Civilization advances by extending the number of important operations which we can perform without thinking about them. Operations of thought are cavalry charges in a battle - they are limited in number, they require fresh horses, and must only be made at decisive moments.

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

Intelligence is quickness to apprehend as distinct form ability, which is capacity to act wisely on the thing apprehended.

The result of teaching small parts of a large number of subjects is the passive reception of disconnected ideas, not illumed with any spark of vitality.

There are no whole truths: all truths are half-truths. It is trying to treat them as whole truths that plays to the devil.