On the Vital Principle/Book 2/Prelude to Chapter 1
After having delineated his subject and quoted and commented on the leading opinions concerning it, Aristotle here reverts to the definition of Vital Principle, which was given partially at the commencement of the inquiry, with the intent of giving to it a signification comprehensive enough to include all living beings; for he had guarded us against limiting the inquiry to the human family. The argument commences as usual with Aristotle, ab ovo,—he attempts, that is, to fix the meaning of essence, matter and form, those primordial entities or conditions, which make up and serve to distinguish all the beings and things of the external world. These very abstruse questions have been alluded to in a former note, and passages were then cited from the Metaphysics and other works for the purpose of obtaining, if possible, precise notions concerning them; but these abstractions are so shadowy, and words so fluctuating, that they seem to elude even the perspicacity of Aristotle, and the ductility of his language. Essence is said to be a genus, to be constitutive, that is, with matter, which, in itself, is no particular thing, of each genus of beings or things; but then it is form, which realises, so to say, that combination by conferring upon it a specific character. For form harmonises with all the organisation of an animal; and every organised body, Cuvier observes, over and above the common qualities of its tissues, has a peculiar form, not only generally and exteriorly, but even down to its minutest details ; and it is " this form which determines the direction of each particular movement, which supports the complicity of its life, constitutes its species, and makes it what it is[1] ."
- ↑ Blainville, 1re leçon.