All morality depends upon our sentiments; and when any action, or quality of the mind, pleases us after a certain manner, we say it is virtuous; and when the neglect, or nonperformance of it, displeases us after a like manner, we say that we lie under an obligation to perform it.
 David Hume, A Treatise of Human Nature (1738). copy citation

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

Context

“The only question then is, whether there be not a manifest absurdity in supposing this act of the mind, and such an absurdity as no man coued fall into, whose ideas are not confounded with prejudice and the fallacious use of language. All morality depends upon our sentiments; and when any action, or quality of the mind, pleases us after a certain manner, we say it is virtuous; and when the neglect, or nonperformance of it, displeases us after a like manner, we say that we lie under an obligation to perform it. A change of the obligation supposes a change of the sentiment; and a creation of a new obligation supposes some new sentiment to arise. But it is certain we can naturally no more change our own sentiments, than the motions of the heavens;” source