since nothing satisfies man's natural desire, except the perfect good which is Happiness.
 Thomas Aquinas, Summa Theologica (1274). copy citation

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Author Thomas Aquinas
Source Summa Theologica
Topic happiness desire
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

“is a good and adequate definition, if it be understood in a certain way; but an inadequate definition if understood in another. For if we understand it simply of all that man desires by his natural appetite, thus it is true that he who has all that he desires, is happy: since nothing satisfies man's natural desire, except the perfect good which is Happiness. But if we understand it of those things that man desires according to the apprehension of the reason, thus it does not belong to Happiness, to have certain things that man desires; rather does it belong to unhappiness, in so far as the possession of such things hinders man from having all that he desires naturally;” source