b. To the Second Reason

300. The second reason too [n.287] has a false major, namely that ‘a relation cannot be founded on a relation’, because according to Euclid Elements of Geometry V def.4, ‘proportionality is a likeness of two proportions’: therefore on a proportion, which formally states a relation, or on its unity, is founded a likeness.

301. And if you argue that ‘likeness is unity in quality’ Metaphysics 5.15.1021a9-12, I say: although in one way ‘what’ is appropriated to the genus of substance, and in the same way ‘same’ and ‘diverse’ (which follow something insofar as ‘what’ is founded on substance), and although ‘equal’ is founded on unity of quantity (taken strictly), ‘like’ on unity of quality - yet taking them in another way ‘what’ is found in every genus, taking the idea of genus very precisely, and ‘what sort of’ is found in every genus (taking form in that genus in the idea of form), and ‘quantity of virtue’ is found in every genus; and so there is found, in this way, in every genus ‘one’, ‘like’, and ‘equal’. For in this way things possessing relations of one species can be said to be alike according to the unity of one relation, just as things possessing one substantial form can be said to be alike according to substance or according to species.

302. And as to what is said [n.262] about the second relation, which is founded on character, namely ‘sign’, I say that if, according to Augustine On Christian Doctrine II ch.1 n.1, “a sign is what, besides the knowledge that it brings to the senses, makes something else come to knowledge” (which is true not only of a sensible sign, taking ‘sense’ strictly for bodily sense, but is true also when taking ‘sense’ generally for cognitive power) - therefore, taking ‘sense’ in this other way for cognitive power, I say thus that there is nothing from the knowledge of which one could come to the knowledge of something else (at least as this is from knowledge of a posterior to a prior), without that posterior thing being able to be called a sign. And thus I concede that on a real relation can be founded the relation of sign to something prior; but such relation not only leads to knowledge of itself but also of something else.

303. And in this way, if someone were to see ‘paternity’ in its foundation, it could be a commemorative sign of a past act of generation. And this is the way it is in the matter at hand.

304. And especially is this not unacceptable, because this relation of sign is only a relation of reason - speaking of a sign instituted at will, of which sort is character with respect to the sacrament or the received sign.

305. As to what is added there [n.287] about the relation of conformity or obligation, it is not cogent; for a religious can, by a vow of religion, be obligated to keeping religion, and he who has done homage can, through the act of doing homage, be obligated to his lord, and in these sort of cases universally [there is obligation] through a preceding promise; and yet there is not there any new absolute form on which the obligation is founded, nor perhaps any relation save one of reason. And so the idea of obligation could be abundantly preserved if it were posited to be a relation of reason, just as filiation in a son could be the idea of some relation to the father (as an obligation to natural love), although it would be possible for it to be filiation alone.

306. And to the proof that then there would be a process to infinity in relations [n.287], it is not valid of real relations, because there is an ultimate relation on which another real relation cannot be founded - just as there is an ultimate accident in beings that cannot be a further subject for another accident; and therefore it does not follow that, if an accident can be in an accident, there is a process to infinity in accidents. However, I readily concede about relations of reason that there can be a process to infinity, because any relation at all, whether real or of reason, can further found another relation of reason.