Every man, by the laws of his nature, necessarily desires or shrinks from that which he deems to be good or bad.
 Baruch Spinoza, Ethics (1677). copy citation

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Author Baruch Spinoza
Source Ethics
Topic desire law
Date 1677
Language English
Reference
Note Translated by R. H. M. Elwes
Weblink http://www.gutenberg.org/files/3800/3800-h/3800-h.htm

Context

“I have taken this course, in order, if possible, to gain the attention of those who believe, that the principle that every man is bound to seek what is useful for himself is the foundation of impiety, rather than of piety and virtue. Therefore, after briefly showing that the contrary is the case, I go on to prove it by the same method, as that whereby I have hitherto proceeded. PROP. XIX. Every man, by the laws of his nature, necessarily desires or shrinks from that which he deems to be good or bad. Proof.—The knowledge of good and evil is (IV. viii.) the emotion of pleasure or pain, in so far as we are conscious thereof; therefore, every man necessarily desires what he thinks good, and shrinks from what he thinks bad.” source