of science be among the number of good thing, or a generation be among evil things, a certain science will be amongst things evil, for instance, if to forget the base acts a person has committed, is among things good, or to remember them, is amongst things evil, to know the base acts which any one has perpetrated, will be amongst evils. It is the same also with the others, for in all there is similar probability.
Moreover, (there is a place) from the more, and the less, and the similarly. For if any one thing of those from another genus is more such, but no one of those is such, neither will what was mentioned be such, e.g. if a certain science is more a good than pleasure, but no science is good, neither will pleasure be. And in the same way from the similarly and the less, for both to subvert and to confirm, will be possible, except (that we may do) both from the similarly, but from the less, only confirm, and not subvert. For if a certain power is similarly good, and science, but a certain power is good, a certain science also is, but if no power, neither is science; still, if a certain power is less a good than science, but a certain power is good, science also is. On the other hand, if no power is good, it is not necessary also that no science should be good, wherefore we can evidently only confirm, from the less.
Notwithstanding, we may not only subvert from another genus, but also from the same, by assuming what is especially such; as if it is admitted that a certain science is good, but it should be shown that prudence is not good, neither will any other be, since what especially seems (good) is not (so). Once more, from hypothesis, when in the same way it is assumed, that if a thing is present or not, with one, it is also or not, with all, as if the soul of man is immortal, that other (souls) also are, but if this is not, that neither are the others. If indeed then a thing is assumed present with a certain one, it must be proved not present with a certain one, since it will follow through the hypothesis that it is present with nothing, but if it is laid down not present with any, we must show that it is present with some one, for thus it will follow that it is present with all. Indeed it is evident that he who makes this hypo-
