Human law has the nature of law in so far as it partakes of right reason
 Thomas Aquinas, Summa Theologica (1274). copy citation

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Author Thomas Aquinas
Source Summa Theologica
Topic reason law
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

“and in this respect it is evident that it is derived from the eternal law. But in so far as it denotes a proneness to sin, it is contrary to the Divine law, and has not the nature of law, as stated above (Q. 91, A. 6) . Reply Obj. 2: Human law has the nature of law in so far as it partakes of right reason; and it is clear that, in this respect, it is derived from the eternal law. But in so far as it deviates from reason, it is called an unjust law, and has the nature, not of law but of violence. Nevertheless even an unjust law, in so far as it retains some appearance of law, though being framed by one who is in power, is derived from the eternal law;” source