genus, have by division a mutual opposition; those, however, are simply simultaneous whose generation is at the same time.[1]
Chap. XIV.—Of Motion.[2]
1. Motion of six kinds. Of motion, there are six species, generation, corruption, increase, diminution, alteration, and change of place.
The other motions then evidently differ from each other, for neither is generation, corruption, nor increase, diminution, nor alteration, change of place, and so of the rest. 2. Alteration questionably relative to the rest, this disproved. In the case of alteration however, there is some doubt, whether it be not sometimes necessary that what is altered, be so, in respect to some one, of the other motions, but this is not true, for it happens that we are altered, as to nearly all the passions, or at least the greater part of them, without any participation of the other motions, for it is not necessary that what is passively moved should be either increased or diminished. Wherefore, alteration will differ from the other motions, since if it were the same, 1st. By no increase or diminution necessarily occurring in what is altered.
2nd, By no change taking place in quality. it would be necessary that what is altered, be forthwith increased or diminished, or follow some of the other motions, but this is not necessary. Similarly, also, what is increased or moved with any other motion, ought to be altered (in quality); but some things are increased which are not so altered, as a square is increased when a gnomon[3] is placed about it, but it has
- ↑ The office of Logic being to guard against ambiguity in the use of terms; it is clear that by nominal division alone, species from the same genus will often have a subordinate opposition, as antagonistic in its nature, as opposite genera; for example, purple, yellow, etc., under colour. Boethius uses division in three senses: 1. Of a genus into species. 2. Of a whole into its parts. 3. Of an equivocal term into its several significations. Cicero. Top. vi. ch., calls the first, divisio, the second partitio. Aristotle approves division by contraries. See Top. vi. 6, 3, de part. Anim. i. 3.
- ↑ Compare the Physics, books iii. v. vi. vii. viii., also Metaph. lib. x. chp. 9, 11, 12. In the 11th ch. of the 10th book, Meta., he defines motion, Ἕ κίνησις ἐνέργεια μὲν εἶναι δοκεῖ τις ἀτελὴς δὲ. Vide also the Scholia, Marc. Ed. Waitz, Ἡ κινησίς ἐστιν ἐξάλλαξις καὶ ἔκστασὶς.
- ↑ The following figure will illustrate this comparison: the use of γνώμον being the ascertainment of right angles.
