Everything of importance has been said before by somebody who did not discover it.

Algebra is the intellectual instrument which has been created for rendering clear the quantitative aspects of the world.

In every age of well-marked transition, there is the pattern of habitual dumb practice and emotion which is passing and there is oncoming a new complex of habit.

The guiding motto in the life of every natural philosopher should be, seek simplicity and distrust it.

Every organism requires an environment of friends, partly to shield it from violent changes, and partly to supply it with its wants.

The consequences of a plethora of half-digested theoretical knowledge are deplorable.

Without adventure all civilization is full of decay. Adventure rarely reaches its predetermined end. Columbus never reached China.