Sex lies at the root of life, and we can never learn to reverence life until we know how to understand sex.

...aesthetic values are changed under the influence of sexual emotion; from the lover's point of view many things are beautiful which are unbeautiful from the point of view of him who is not a lover, and the greater the degree to which the lover is swayed by his passion the greater the extent to which his normal aesthetic standard is liable to be modified.

Imagination is a poor substitute for experience.

It is becoming clear that the old platitudes can no longer be maintained, and that if we wish to improve our morals we must first improve our knowledge.

It is here [in mathematics] that the artist has the fullest scope of his imagination.

Where there is most labour there is not always most life.

The prevalence of suicide, without doubt, is a test of height in civilization; it means that the population is winding up its nervous and intellectual system to the utmost point of tension and that sometimes it snaps.