Pessimism leads to weakness. Optimism leads to power.

The unrest which keeps the never stopping clock of metaphysics going is the thought that the nonexistence of this world is just as possible as its existence.

The sway of alcohol over mankind is unquestionably due to its power to stimulate the mystical faculties of human nature, usually crushed to earth by the cold facts and dry criticisms of the sober hour.

Our errors are surely not such awfully solemn things. In a world where we are so certain to incur them in spite of all our caution, a certain lightness of heart seems healthier than this excessive nervousness on their behalf.

Our acts of voluntary attending, as brief and fitful as they are, are nevertheless momentous and critical, determining us, as they do, to higher or lower destinies.

Deepest principle of human nature is to be appreciated.

Our ideas must agree with realities, be such realities concrete or abstract