What he really esteems is what ought to guide his conduct; for to suggest that a rational being ought to do what he feels to be wrong, or ought to pursue what he genuinely thinks is worthless, would be to impugn that man's rationality and to discredit one's own.
 George Santayana, The Life of Reason (1905). copy citation

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Author George Santayana
Source The Life of Reason
Topic rationality discredit
Date 1905
Language English
Reference
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Weblink http://www.gutenberg.org/files/15000/15000-h/15000-h.htm

Context

“It is the logic of an autonomous will.
This method, the Socratic method, consists in accepting any estimation which any man may sincerely make, and in applying dialectic to it, so as to let the man see what he really esteems. What he really esteems is what ought to guide his conduct; for to suggest that a rational being ought to do what he feels to be wrong, or ought to pursue what he genuinely thinks is worthless, would be to impugn that man's rationality and to discredit one's own. With what face could any man or god say to another: Your duty is to do what you cannot know you ought to do; your function is to suffer what you cannot recognise to be worth suffering? Such an attitude amounts to imposture and excludes society; it is the attitude of a detestable tyrant, and any one who mistakes it for moral authority has not yet felt the first heart-throb of philosophy.
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