What is natural and essential to any thing is, in a manner, expected; and what is expected makes less impression, and appears of less moment, than what is unusual and extraordinary.
 David Hume, A Treatise of Human Nature (1738). copy citation

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

Context

“Thus as the nature of a river consists in the motion and change of parts; though in less than four and twenty hours these be totally altered; this hinders not the river from continuing the same during several ages. What is natural and essential to any thing is, in a manner, expected; and what is expected makes less impression, and appears of less moment, than what is unusual and extraordinary. A considerable change of the former kind seems really less to the imagination, than the most trivial alteration of the latter; and by breaking less the continuity of the thought, has less influence in destroying the identity.
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