regarded only as the seat or source of the touch; and yet the flesh was said to be the origin[1] and very body of an animal. The strength[2] of all animals is, he adds, in the tendons (ἡ ἰσχὺς ἐν τοῖς νεύροις), and, therefore, strength is greatest when they are full grown; for the young have weak joints and deficient sinews.
Since the Vital Principle of animals has been defined by the two faculties of judgment (which is the office of thought with sentient perception), and of locomotion, let us now, having dwelt sufficiently upon sensation and mind, proceed to consider, with respect to the motor power, what part of the Vital Principle it may be. Let us consider, that is, whether it is a part of Vital Principle and separate from it, substantively or abstractedly, or whether it is Vital Principle as a whole; and if it be a part, whether it is something peculiar and exclusive of those usually attributed to Vital Principle, and which have been alluded to, or whether it is to be considered as one of them.
But a difficulty at once presents itself, both in
