When a man desires a thing and reckons that he can get it, he believes that he can get it, he believes that he will get it
 Thomas Aquinas, Summa Theologica (1274). copy citation

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Author Thomas Aquinas
Source Summa Theologica
Topic 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

“according to Ecclus. 51:10, "I looked for the succor of men." Wherefore the movement of hope is sometimes called expectation, on account of the preceding inspection of the cognitive power. Reply Obj. 2: When a man desires a thing and reckons that he can get it, he believes that he can get it, he believes that he will get it; and from this belief which precedes in the cognitive power, the ensuing movement in the appetite is called confidence. Because the movement of the appetite takes its name from the knowledge that precedes it, as an effect from a cause which is better known;” source