Objection 1: It would seem that a notional act can be directed to several Persons, so that there may be several Persons begotten or spirated in God. For whoever has the power of begetting can beget. But the Son has the power of begetting. Therefore He can beget.
 Thomas Aquinas, Summa Theologica (1274). copy citation

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Author Thomas Aquinas
Source Summa Theologica
Topic power God
Date 1274
Language English
Reference
Note Translated by Fathers of the English Dominican Province
Weblink http://www.gutenberg.org/cache/epub/17611/pg17611-images.html

Context

“Wherefore in respect of the essence, which is signified, the power of begetting is common to the three persons: but in respect of the notion that is connoted, it is proper to the person of the Father. _______________________
SIXTH ARTICLE [I, Q. 41, Art. 6]
Whether Several Persons Can Be the Term of One Notional Act?
Objection 1: It would seem that a notional act can be directed to several Persons, so that there may be several Persons begotten or spirated in God. For whoever has the power of begetting can beget. But the Son has the power of begetting. Therefore He can beget. But He cannot beget Himself: therefore He can beget another son. Therefore there can be several Sons in God.
Obj. 2: Further, Augustine says (Contra Maxim. iii, 12) : "The Son did not beget a Creator: not that He could not, but that it behoved Him not."
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