CHAPTER VI.
DEFINITIONS, GENERA, AND SPECIES.
The introductions and sources of questions are about these points and in them.
But before definitions, and demonstrations, and divisions, it must be propounded in what ways the question is stated; and equivocal terms are to be treated; and synomyms stated accurately according to their significations.
Then it is to be inquired whether the proposition belongs to those points, which are considered in relation to others, or is taken by itself. Further, If it is, what it is, what happens to it; or thus, also, if it is, what it is, why it is. And to the consideration of these points, the knowledge of Particulars and Universals, and the Antecedents and the Differences, and their divisions, contribute.
Now, Induction aims at generalization and definition; and the divisions are the species, and what a thing is, and the individual. The contemplation of the How adduces the assumption of what is peculiar; and doubts bring the particular differences and the demonstrations, and otherwise augment the speculation and its consequences; and the result of the whole is scientific knowledge and truth.
Again, the summation resulting from Division becomes Definition. For Definition is adopted before division and after: before, when it is admitted or stated; after, when it is demonstrated. And by Sensation the Universal is summed up from the Particular. For the starting point of Induction is Sensation; and the end is the Universal.
Induction, accordingly, shows not what a thing is, but that it is, or is not. Division shows what it is; and Definition similarly with Division teaches the essence and what a thing is, but not if it is; while Demonstration explains the three points, if it is, what it is, and why it is.
There are also Definitions which contain the Cause. And since it may be known when we see, when we see the Cause; and Causes are four—the matter, the moving power, the species, the end; Definition will be fourfold.
