Having thus summarily recounted whatever has been said upon the Vital Principle, let us repeat that it is, in some sense, all things which are; for things are the subjects either of sentient perception or of thought, and knowledge is, in some sense, things known, as sensation is things sensually perceived. But let us inquire how this is to be understood—Knowledge, then, like sensation is divided, when in potentiality, into things in potentiality, when in reality, into things in reality; and the sentient and the cogitative faculties of Vital Principle are, when in potentiality, identical with thoughts and objects of perception, in potentiality. But the question here must necessarily refer either to things or the forms of things; but the things themselves they cannot be, as it is not a stone but the form of a stone which is in the Vital Principle. Thus, the Vital Principle is, as it were, a hand, for as a hand is the instrument of instruments, so the mind is the form of forms, and sensation the form of things sensually perceived. Since there is, seemingly, nothing separate from perceptible magnitude, it must be admitted that all subjects of cogitation are in perceptible forms, as well those termed abstractions as those which relate to the conditions and changes of the objects of perception. And, therefore, if a being were without sentient perception, he could neither learn nor understand; as for reflexion the individual must be able to call up an image of some sort, and images are kinds of sensations, excepting that they are immaterial. Imagination, on the other hand, is something different from affirmation and negation, for the true or the false is but a complication of thoughts. But by what are primal thoughts to be distinguished from such as are derived from images? Other thoughts, however, are not images, and yet without images they could not be produced.