se_, but a _Correlatum_ to certain _superstrata_, determined or undetermined: now the _Correlatum_ is one of the pair implicated directly or indirectly in all Relation; and it is in fact specified by Aristotle as one variety of the Category _Ad Aliquid_.[88] We see therefore that the idea of Relativity attaches to the first of the ten Categories, as well as to the nine others. The inference from these observations is, that Relation or Relativity, understood in the large sense which really belongs to it, ought to be considered rather as an Universal, comprehending and pervading all the Categories, than as a separate Category in itself, co-ordinate with the other nine. It is the condition and characteristic of the work of predication generally; the last analysis of which is into Subject and Predicate, in reciprocal implication with each other. I remark that this was the view taken of it by some well-known Peripatetic commentators of antiquity;[89] by Andronikus, for example, and by Ammonius after him. Plato, though he makes no attempt to draw up a list of Categories, has an incidental passage respecting Relativity;[90] conceiving it in a very extended sense, apparently as belonging more or less to all predicates. Aristotle, though in the Categoriæ he gives a narrower explanation of it, founded upon grammatical rather than real considerations, yet intimates in other places that predicates ranked under the heads of _Quale_, _Actio_, _Passio_, _Jacere_, &c., may also be looked at as belonging to the head of _Ad Aliquid_.[91] This latter, moreover, he himself declares elsewhere to be _Ens_ in the lowest degree, farther removed from the _Prima Essentia_ than any of the other Categories; to be more in the nature of an appendage to some of them, especially to _Quantum_ and _Quale_;[92] and to presuppose, not only the _Prima Essentia_ (which all the nine later Categories presuppose), but also one or more of the others, indicating the particular mode of comparison or Relativity in each case affirmed. Thus, under one aspect, Relation or Relativity may be said to stand _prius naturâ_, and to come first in order before all the Categories, inasmuch as it is implicated with the whole business of predication (which those Categories are intended to resolve into its elements), and belongs not less to the mode of conceiving what we call the Subject, than to the mode of conceiving what we call its Predicates, each and all. Under another aspect, Relativity may be said to stand last in order among the Categories--even to come after the adverbial Categories _Ubi et Quando_; because its _locus standi_ is dim and doubtful, and because every one of the subordinate predicates belonging to it may be seen to belong to one or other of the remaining Categories also. Aristotle remarks that the Category _Ad Aliquid_ has no peculiar and definite mode of generation corresponding to it, in the manner that Increase and Diminution