(1) Since not only do logicians use the above words of second intention,1 but also many other terms of second intention, and also of second imposition, often come into use, [therefore,] I now want to treat some of them briefly, in order that students not be slowed down in their search for truth on account of ignorance of the signification of these [terms].
(2) Among the terms logicians use, some are common to all universal [terms], others are proper to some of them, some belong to some of them taken together, others belong to one [universal term] with respect to another one. The terms that belong to several [universal terms] taken together are ‘definition’ and ‘description’.
(3) ‘Definition’ is taken in two senses. One kind is a real definition,2 and the other kind is a nominal definition.3
(4) ‘Real definition’ is taken in two senses. [In one sense, it is taken] broadly, and in this sense it includes the [real] definition taken strictly, and also the descriptive definition. In another sense, the name ‘[real] definition’ is taken strictly, and in this sense it is a brief discourse expressing the whole na- ture of the thing and not indicating anything extrinsic to the defined thing.
(5) This can come about in two ways. Sometimes in such a discourse there occur oblique cases [of names] expressing the essential parts of the thing. For example, when I define man by saying ‘A man is a substance composed of a body and an intellective soul’. For the oblique [forms] ‘of a body’ and ‘of an intellective soul’4 express the parts of the thing. This [kind of definition] can be called a “physical definition”.
(6) There is another [kind of] definition in which no oblique case occurs, but instead the genus is put in the nominative, and likewise the difference or differences expressing the parts of the defined thing, in the way in which ‘white’ expresses whiteness, are put in the nominative. Therefore, just as ‘white’, even though it expresses a whiteness, nevertheless does not supposit for a whiteness but rather only for the subject of a whiteness, so [too] the differences [in a definition like this], even though they express parts of the thing, nevertheless do not supposit for the parts of the thing, but rather [supposit] precisely for the whole composed of those parts. The definition of man: ‘rational animal’, or ‘rational sensitive5 besouled substance’ is like this. For the differences ‘besouled’, ‘sensitive’, [and] ‘rational’ supposit for a man, because a man is rational, besouled and sensitive. Nevertheless, they convey part of the man, just as the abstract [terms] corresponding to them convey a part or parts of a man — although not in the same way. This [kind of definition] can be called a “metaphysical definition”, because the metaphysician would define man in this way.
(7) There can be no other [kind of] definition besides these two, except perhaps the [kind such that] each part of it is in more [than the defined] and the whole [is] equal [to the defined].6 Therefore, what some [people] say is ridiculous, that one kind of definition of man is logical, another kind physical, [and] another kind metaphysical. For the logician, since he does not treat of man insofar as he does not treat of things that are not signs, does not have to define man. Rather he has to teach how the other sciences that do treat of man should define him. Therefore, the logician should not give any definition of man, except perhaps by way of example. And in that case the definition that is given by way of example should be [either] a physical one or a metaphysical one.
(8) And just as it is pointless to say that one kind of definition is physical, another kind metaphysical, [and] another kind logical, so [too] it is pointless to say that one kind of man is physical, another kind metaphysical, [and] another kind logical.
(9) Likewise, even though it could be said that one kind of definition of man is physical [and] another kind metaphysical, on account of the difference in the parts of these expressions, nevertheless it is completely unreasonable and false to claim that one kind of man is physical [and] another kind [is] metaphysical. For if one kind of man is physical [and] another kind [is] metaphysical, either (a) [this] is understood [in the sense] that there is some thing outside the soul, some true substance, that is a physical man, and another true substance that is a metaphysical man, or else (b) it is understood [in the sense] that some concept of the mind or utterance is a physical man and another one is a metaphysical [man].