The mind can never exert itself in any action, which we may not comprehend under the term of perception
 David Hume, A Treatise of Human Nature (1738). copy citation

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Author David Hume
Source A Treatise of Human Nature
Topic perception action
Date 1738
Language English
Reference
Note
Weblink http://www.gutenberg.org/files/4705/4705-h/4705-h.htm

Context

“Without this advantage I never should have ventured upon a third volume of such abstruse philosophy, in an age, wherein the greatest part of men seem agreed to convert reading into an amusement, and to reject every thing that requires any considerable degree of attention to be comprehended. It has been observed, that nothing is ever present to the mind but its perceptions; and that all the actions of seeing, hearing, judging, loving, hating, and thinking, fall under this denomination. The mind can never exert itself in any action, which we may not comprehend under the term of perception; and consequently that term is no less applicable to those judgments, by which we distinguish moral good and evil, than to every other operation of the mind. To approve of one character, to condemn another, are only so many different perceptions.” source