In the beginning of this chapter we did indeed contend that the “compulsion” which prompts to artistic activity is too strong to be even compared with the passion for sports and games. But this superiority may of course be explained as a result of some peculiarity of this special kind of play. As a matter of fact art is, in a far higher degree than any of the sports and games, able to satisfy the _greatest_ and most _fundamental_ instincts of man. Groos has tried to prove that the artistic motives which in all times have been most popular, offer to the spectator as well as to the producer an opportunity for warlike and erotic stimulation;[39] and Guyau had already remarked how important a part the moods of war, or rather of struggle, play in all enjoyment of art.[40] It is easy to understand the eager prosecution of an activity which thus affords free, if imaginary, exercise for instincts and tendencies which would otherwise be thwarted by the narrow restrictions of social life. We are all animals in captivity, and we eagerly seize every kind of vicarious function which can give at least a memory of the life from which we are excluded. At lower stages of social evolution, where instincts are more in harmony with life, the play-element in art must evidently be of still greater importance. Artistic production and artistic enjoyment provide exercise for those very functions which are most important in real life. Art fulfils a great social mission, and is developed in subservience to the struggle for life. The play-theory, as formulated by Professor Groos, affords, therefore, in many cases an explanation of the high artistic level reached by the lower tribes. In our historical treatment of primitive dances and dramas we shall be continually obliged to have recourse to this theory. And it will thus appear that it is no deficient appreciation of its importance which compels us to look elsewhere for an explanation for the artistic impulse.