Nature has color-coded groups of individuals so that statistically reliable predictions of their adaptability to intellectual rewarding and effective lives can easily be made and profitably used by the pragmatic man-in-the street.

I am overwhelmed by an irresistible temptation to do my climb by moonlight and unroped. This is contrary to all my rock climbing teaching & does not mean poor training, but only a strong-headedness.

If you take a bale of hay and tie it to the tail of a mule and then strike a match and set the bale of hay on fire, and if you then compare the energy expended shortly thereafter by the mule with the energy expended by yourself in the striking of the match, you will understand the concept of amplification.

Regret is unnecessary. Think before you act.

The major cause for American Negroes intellectual and social deficits is hereditary and racially genetic in origin and thus not remedial to a major degree by improvement in environment.