The dog plays at biting the hand of his master, and actually takes the member between his teeth and mumbles it; but all the while he stops short of painful pressure, and goes through a series of characteristic attitudes which show that he distinguishes very clearly between this play biting and the real.

If perchance the master shows signs of being hurt, the dog falls into attitudes of sorrow, and apologizes fulsomely.

So also when the animals play together, a vigorous squeal from a companion who is "under" generally brings him his release.
The principal interest of this make-believe consciousness is that it is considered by many to be an essential ingredient of AEsthetic feeling.

A work of art is said to have its effect through its tendency to arouse in us a make-believe acceptance of the scene or motive presented, while it nevertheless remains contrasted with the realities of our lives.

If this be true, the interesting question arises how far the animals also have the germs of AEsthetic feeling in their make-believe situations.