§ 65. Gymnastics is the art of systematic training of the muscular system. The action of the voluntary muscles, which are regulated by the nerves of the brain, in distinction from the involuntary automatic muscles depending on the spinal cord, while they are the means of man's intercourse with the external world, at the same time re-act upon the automatic muscles in digestion and sensation. Since the movement of the muscular fibres consists in the change of contraction and expansion, it follows that Gymnastics must bring about a change of movement which shall both contract and expand the muscles. § 66. The system of gymnastic exercise of any nation corresponds always to its way of fighting. So long as this consists in the personal struggle of a hand-to-hand contest, Gymnastics will seek to increase as much as possible individual strength and adroitness. As soon as the far-reaching missiles projected from fire-arms become the centre of all the operations of war, the individual is lost in a body of men, out of which he emerges only relatively in sharp-shooting, in the charge, in single contests, and in the retreat. Because of this incorporation of the individual in the one great whole, and because of the resulting unimportance of personal bravery, modern Gymnastics can never be the same as it was in ancient times, even putting out of view the fact that the subjectiveness of the modern spirit is too great to allow it to devote so much attention to the care of the body, and the admiration of its beauty, as was given by the Greeks.