in which it is naturally adapted to be generated, either simply, or in which first, it is adapted to be generated. Thus if stating ignorance to be privation, a person has not said that it is a privation of science, or has not added in what it is naturally adapted to be produced, or having added it, has not assigned in what first, as that it is not in the reasoning faculty, but in man or soul, for if he has not done some one of these, he commits an error. So also if he should not have said that blindness is privation of sight in the eye, for it is requisite that he who well assigns what (privation) is, should also assign of what it is the privation, and again, what that is, which is deprived.
Observe, also, whether a person has defined by privation, that which is not predicated according to privation, which fault they will appear to commit in the definition of ignorance, who do not speak of ignorance according to negation. For that which has not science does not seem to be ignorant, but rather that which is deceived, hence we neither say, that inanimate things nor children are ignorant, so that ignorance is not predicated according to the privation of science.
Chapter 10
Again, (examine) whether similar cases of the definition agree with similar cases of the noun, for instance, if the beneficial is what produces health, whether beneficially be productively, and that was beneficial, which was productive of health.
Besides observe, whether the definition stated accords to the idea, since in some things this does not happen, as when Plato in his definition of animals, adds "mortals," for idea will not be mortal; for instance, man-self, wherefore the definition will not suit the idea. In short, it is necessary that the definition