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.

Value is coextensive with reality.

Inventive genius requires pleasurable mental activity as a condition for its vigorous exercise

What we perceive as the present is the vivid fringe of memory tinged with anticipation.

Learning preserves the errors of the past as well as its wisdom.

Our minds are finite, and yet even in these circumstances of finitude we are surrounded by possibilities that are infinite, and the purpose of life is to grasp as much as we can out of that infinitude.

In a sense, knowledge shrinks as wisdom grows, for details are swallowed up in principles. The details for knowledge which are important, will be picked up ad hoc in each avocation of life, but the habit of the active utilization of well-understood principles is the final possession of WISDOM.