The Basic Works of Aristotle (Modern Library Classics) by Richard Mckeon Read Free Book Online

entered into a different state. Similarly that which was white becomes black, and that which was bad good, by a process of change; and in the same way in all other cases it is by changing that substances are capable of admitting contrary qualities. But statements and opinions themselves remain unaltered in all respects: it is by the alteration in the facts of the case that the contrary quality comes to be theirs. (35) The statement ‘he is sitting’ remains unaltered, but it is at one time true, at another false, according to circumstances. [4b] What has been said of statements applies also to opinions. Thus, in respect of the manner in which the thing takes place, it is the peculiar mark of substance that it should be capable of admitting contrary qualities; for it is by itself changing that it does so.
    If, then, a man should make this exception and contend that statements and opinions are capable of admitting contrary qualities, his contention is unsound. For statements and opinions are said (5) to have this capacity, not because they themselves undergo modification,but because this modification occurs in the case of something else. The truth or falsity of a statement depends on facts, and not on any power on the part of the statement itself of admitting contrary qualities. (10) In short, there is nothing which can alter the nature of statements and opinions. As, then, no change takes place in themselves, these cannot be said to be capable of admitting contrary qualities.
    But it is by reason of the modification which takes place within the substance itself that a substance is said to be capable of admitting contrary qualities; for a substance admits within itself either disease or health, (15) whiteness or blackness. It is in this sense that it is said to be capable of admitting contrary qualities.
    To sum up, it is a distinctive mark of substance, that, while remaining numerically one and the same, it is capable of admitting contrary qualities, the modification taking place through a change in the substance itself.
    Let these remarks suffice on the subject of substance.
    6      Quantity is either discrete or continuous. (20) Moreover, some quantities are such that each part of the whole has a relative position to the other parts: others have within them no such relation of part to part.
    Instances of discrete quantities are number and speech; of continuous, lines, surfaces, solids, and, besides these, time and place.
    In the case of the parts of a number, (25) there is no common boundary at which they join. For example: two fives make ten, but the two fives have no common boundary, but are separate; the parts three and seven also do not join at any boundary. Nor, to generalize, would it ever be possible in the case of number that there should be a common boundary among the parts; (30) they are always separate. Number, therefore, is a discrete quantity.
    The same is true of speech. That speech is a quantity is evident: for it is measured in long and short syllables. I mean here that speech which is vocal. Moreover, it is a discrete quantity, for its parts have no common boundary. (35) There is no common boundary at which the syllables join, but each is separate and distinct from the rest.
    [5a] A line, on the other hand, is a continuous quantity, for it is possible to find a common boundary at which its parts join. In the case of the line, this common boundary is the point; in the case of the plane, it is the line: for the parts of the plane have also a common boundary. Similarly you can find a common boundary in the case of the parts of a solid, (5) namely either a line or a plane.
    Space and time also belong to this class of quantities. Time, past, present, and future, forms a continuous whole. Space, likewise, is a continuous quantity: for the parts of a solid occupy a certain space, and these have a common boundary; it follows that the parts of space also, which are occupied by the parts of the solid, (10) have