Every power that is divided in itself is weakened.
 Thomas Aquinas, Summa Theologica (1274). copy citation

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Author Thomas Aquinas
Source Summa Theologica
Topic power
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

“Nevertheless the very fact that anger soon spends itself proves the strength of its fervor: for as a great fire is soon spent having burnt up all the fuel; so too anger, by reason of its vehemence, soon dies away. Reply Obj. 3: Every power that is divided in itself is weakened. Consequently if a man being already angry with one, becomes angry with another, by this very fact his anger with the former is weakened. Especially is this so if his anger in the second case be greater:” source