Indeed, looked at from the side of the development of the brain, we see that there is no break between man and the animals in the laws of organization, but that the difference is one of evolution.
Later on in the life of the child we find another contrast connected with the difference of social life and organization as between the animals and man.

The animals probably do not have a highly organized sense of Self as man does; and the reason doubtless is that such a Self-consciousness is the outcome of life and experience in the very complex social relations in which the human child is brought up, and which he alone is fitted by his inherited gifts to sustain.
_The Play of Animals._--Another of the most interesting questions of animal life is that which concerns their plays.

Most animals are given to play.

Indeed that they indulge in a remarkable variety of sports is well known even to the novice in the study of their habits.

Beginning when very young, they gambol, tussle, leap, and run together, chase one another, play with inanimate objects, as the kitten with the ball, join in the games of children and adults, as the dog which plays hide and seek with his little master, and all with a knowingness and zest which makes them the best of companions.