The adjective kind is derived from the nouns kind and kin, probably meaning originally the behavior proper toward one's relatives. Kindness to one's fellows is a necessary factor in gregariousness. It, too, must have grown out of family life, especially the mother's care for her offspring. Thorndike uses the title, "motherly behavior and kindliness," though without restricting it to mothers:

Modern philanthropy and acceptance of the brotherhood of man as a living creed rests at bottom on the original tendency, strongest by far in women, to hold, cuddle, enjoy the welfare of, and relieve the distress of, young and helpless human beings; and upon a more diffused original kindliness toward all human kind. . . .

Boys and men are not by nature entirely lacking in mothering behavior as traditional opinions declare. To give a little child food, to smile sympathetically at its play, and to drive off its enemies are perhaps as instinctive in the boy or man as the tendencies to clasp and fondle it are in woman.

The more diffuse kindliness, sympathy or pity consists, in the first place, of attentiveness to a human being manifestly hungry, frightened or in pain, and active measures to relieve him. In the second place it is a positive satisfaction at, and approval of, happy or contented behavior in other men. - Thorndike, Education, 84, 85.

James discussed this subject under the title of "Sympathy":

Some forms of sympathy, that of a mother with child, for example, are surely primitive, and not intelligent forecasts of board and lodging and other support to be reaped in old age. Danger to the child blindly and instantaneously stimulates the mother to actions of alarm or defense. Menace or harm to the adult beloved or friend excites us in a corresponding way, often against all the dictates of prudence. It is true that sympathy does not necessarily follow from the mere fact of gregariousness. Cattle do not help a wounded comrade; on the contrary they are more likely to dispatch him. But a dog will lick another sick dog, and even bring him food; and the sympathy of monkeys is proved by many observations to be strong. In man, then, we may lay it down that the sight of suffering or danger to others is a direct exciter of interest and an immediate stimulus, if no complication hinders, to acts of relief. - James, Psychology, Vol. II, pp. 410, 411.