St. Thomas Aquinas (1225-1274)

Summa Theologica (1267-1273, incomplete)

First Part, Question 5, Article 4: “Whether Good has the aspect of a Final Cause (Great Books, vol. 17, p. 26)

“Beauty and good in a subject are the same, for they are based upon the same thing, namely, the form; and consequently good is praised as beauty. But they differ logically, for good properly relates to the appetite (good being what all things desire), and therefore it has the aspect of an end (for the appetite is a kind of movement towards a thing). On the other hand, beauty relates to the knowing power, for beautiful things are those which please when seen. Hence beauty consists in due proportion, for the senses delight in things duly proportioned, as in what is after their own kind—because even sense is a sort of reason, just as is every knowing power. Now, since knowledge is by assimilation, and likeness relates to form, beauty properly belongs to the nature of a formal cause.” [See below on Aristotle’s four “causes”]

Second Part, Part 1, Question 27, Article 1: “Whether Good is the Only Cause of Love” (Great Books, vol. 17, p. 737)

“The beautiful is the same as the good, and they differ in aspect only. For since good is what all seek, that which calms the desire is implied in the notion of good, while that which calms the desire by being seen or known pertains to the notion of the beautiful. Consequently those senses especially have to do with the beautiful which are the best avenues of knowledge, namely, sight and hearing, as ministering to reason; for we speak of beautiful sights and beautiful sounds….Thus it is evident that beauty adds to goodness a relation to the knowing power, so that good means that which pleases absolutely the appetite, while the beautiful is something pleasant to apprehend.”

Aristotle’s four “causes”:

efficient cause: “the source of change” (Metaphysics, Book 1, Chap. 3; Great Books, vol. 7, p. 501); “the primary source of change” (Physics, Book 2, Chap. 3; Great Books, vol. 7, p. 271); the agent that initiates the process of change (Britannica)

final cause: “the end [purpose, outcome] or ‘that for the sake of which’ a thing is done” (Physics, Book 2, Chap. 3; Great Books, vol. 7, p. 271); “the purpose and the good (for this is the end of all generation and change” (Metaphysics, Book 1, Chap. 3; Great Books, vol. 7, p. 501)

formal cause: “the form or the archetype, i.e. the statement of the essence” (Physics, Book 2, Chap. 3; Great Books, vol. 7, p. 271); the feature whose acquisition determines the nature of change (Britannica)

material cause: “that out of which a thing comes to be and which persists [through change]” (Physics, Book 2, Chap. 3; Great Books, vol. 7, p. 271); “the matter or substratum [which persists through change]” (Metaphysics, Book 1, Chap. 3; Great Books, vol. 7, p. 501)