The ability to play is one of ...

The ability to play is one of the principal criteria of mental health.
 Ashley Montagu

Quotes from the same author

The benefits to the mother of immediate breastfeeding are innumerable, not the least of which after the weariness of labor and birth is the emotional gratification, the feeling of strength, the composure, and the sense of fulfillment that comes with the handling and suckling of the baby.
 Ashley Montagu
Human beings are the only creatures who are able to behave irrationally in the name of reason.
 Ashley Montagu
The basic fact is simple: life begins not at birth, but conception.
 Ashley Montagu
One goes through school, college, medical school and one's internship learning little or nothing about goodness but a good deal about success.
 Ashley Montagu
Scientists do not believe in fundamental and absolute certainties. For the scientist, certainty is never an end, but a search; not the ordering of certainty, but its exploration. For the scientist, certainty represents the highest degree of probability.
 Ashley Montagu