But all desire delight; both wise and foolish, and even irrational creatures. Therefore delight is the best of all. Therefore happiness, which is the supreme good, consists in pleasure.
 Thomas Aquinas, Summa Theologica (1274). copy citation

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Author Thomas Aquinas
Source Summa Theologica
Topic happiness pleasure
Date 1274
Language English
Reference
Note Translated by Fathers of the English Dominican Province
Weblink http://www.gutenberg.org/cache/epub/17897/pg17897-images.html

Context

“Now this is pleasure: and a sign of this is that delight so far absorbs man's will and reason, that it causes him to despise other goods. Therefore it seems that man's last end, which is happiness, consists principally in pleasure.
Obj. 3: Further, since desire is for good, it seems that what all desire is best. But all desire delight; both wise and foolish, and even irrational creatures. Therefore delight is the best of all. Therefore happiness, which is the supreme good, consists in pleasure. On the contrary, Boethius says (De Consol. iii) : "Any one that chooses to look back on his past excesses, will perceive that pleasures had a sad ending: and if they can render a man happy, there is no reason why we should not say that the very beasts are happy too."
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