IV. To the Arguments

150. [To the Principal Arguments] - When it is argued to the principal from Augustine On the Trinity [n.46] I reply: Augustine subjoins in the same place: “as if one thing there were substance and another were person.”

Likewise, I concede that a person is not properly said to be from the essence absolutely, but when adding along with the substance some originating person it is well said that some originated person is of the substance of that person, such that this proposition ‘the Son is from the divine essence’ is not to be conceded in the way that this proposition is ‘the Son is from the substance of the Father’, because by the second is expressed consubstantiality and origination, on account of the genitive [‘of the Father’] construed with the causal case of the preposition [‘from the substance’], - but by the first nothing originating is indicated.

151. To the other [n.47] one must say that although Augustine says the Son is ‘Son of the substance of the Father’ (On the Trinity XV ch.19 n.37, n.49), and a certain doctor [Henry] says this proposition is a proper one, - yet it seems more probable that whenever a relative [‘Son’] is construed with something [‘substance’] in that sort of causal relationship [‘of’] in which something naturally terminates the relative as its correlative, then it is construed with it [‘Son of the substance’] precisely as with its correlative [‘Son of the Father’]. - An example. ‘Father’ is construed with the relative in the genitive case [‘of the father’], ‘similar’ in the dative case [‘similar to...’], ‘greater’ in the ablative case [‘greater than.’]. According to common speech, it seems that with whatever ‘such a [determinate] relative’ is construed in ‘such a causal [genitive] case’, it is indicated to be the correlative of the relative [sc. ‘son of the father/of man/of substance’]; for we do not say ‘this dog is the son of a man’ because it is a son and is of a man as of the dog’s master, such that ‘of a man’ is construed with ‘dog’ by force of possession or possessor, but ‘of a man’ seems to indicate that it is construed with ‘dog’ in the idea of relation, as with ‘of the father’.In other words [to quote the note of the editors of the Vatican edition], although we can say that a dog is a son [of some dog] and is of a man [as of its master], common speech does not allow us to go on to say ‘the dog is a son of a man’ because here ‘of a man’ indicates paternity and not, as it did originally, mastership. ²⁶

152. Thus therefore in the phrase ‘the Son of the essence’, it seems that essence is taken as the correlative of the relative with which it is construed. - And then the authority of Augustine [n.151] ought to be expounded as he himself expounds it [sc. and not as Henry does, n.49]: “‘of the Son of his charity,’ - that is ‘of the Son of his delight’.”

153. And then to this argument [n.151]: when it is argued that on the phrase ‘from the essence’ follows the phrase that he is ‘of the essence’, - I deny the consequence, because the consequent indicates that the relation between the Son and the essence is like that of a correlative; and this the antecedent does not indicate, but it only indicates consubstantiality in the essence, along with origination, indicated in the thing that is construed with essence.

154. To the final one [n.48] I say that ‘from’ [as in ‘the Son is from the substance of the Father’] does not indicate only identity, but it indicates identity of the noun it governs [‘substance’] (and this in the idea of form) and distinction of that which is added to that noun [‘of the Father’] as originating principle, in the way said before [n.99].

155. [To the arguments for the opposite] - To the arguments for the opposite: To that from On the Trinity XV [n.49] the response has been given [n.152].

156. To the one from Against Maximinus [n.50] the response is plain too from what has been said [nn.98-101].

157. To the final one [n.51], about ‘son’ in the case of creatures, - the response is plain from what was said in the solution of the question, because the ‘from’, which pertains to the idea of filiation, does not state the idea of material cause [n.104], but rather it is enough if that from which the son is be a form common to father and son and be, not the subject of generation, but the formal term of it [n.105].