How little perfect sincerity is to be expected even from otherwise honest persons whenever their interests are in any way concerned we can gather from the fact that we so often deceive ourselves when hope bribes us, or fear befools us, or suspicion torments us, or vanity flatters us, or an hypothesis blinds us, or a small aim which is close at hand injures a greater but more distant one
 Arthur Schopenhauer, The World as Will and Representation (1819). copy citation

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Author Arthur Schopenhauer
Source The World as Will and Representation
Topic sincerity suspicion
Date 1819
Language English
Reference
Note Translated by R. B. Haldane and J. Kemp
Weblink http://www.gutenberg.org/files/40097/40097-h/40097-h.html

Context

“Lastly, the fact is also in point here, that when advice is given the slightest aim or purpose of the adviser generally outweighs his insight, however great it may be; therefore we dare not assume that he speaks from the latter when we suspect the existence of the former. How little perfect sincerity is to be expected even from otherwise honest persons whenever their interests are in any way concerned we can gather from the fact that we so often deceive ourselves when hope bribes us, or fear befools us, or suspicion torments us, or vanity flatters us, or an hypothesis blinds us, or a small aim which is close at hand injures a greater but more distant one; for in this we see the direct and unconscious disadvantageous influence of the will upon knowledge. Accordingly it ought not to surprise us if in asking advice the will of the person asked directly dictates the answer even before the question could penetrate to the forum of his judgment.” source