When you wish to obtain some concession from a man’s self-love, you must avoid even the appearance of wishing to wound it.
 Alexandre Dumas, The Count of Monte Cristo (1845). copy citation

Context

““Ah, but the friends of today are the enemies of tomorrow; Beauchamp, for instance.” “So you recommend——” “I recommend you to be prudent.” “Then you advise me to go alone to Beauchamp?” “I do, and I will tell you why. When you wish to obtain some concession from a man’s self-love, you must avoid even the appearance of wishing to wound it.” “I believe you are right.” “I am glad of it.” “Then I will go alone.” “Go; but you would do better still by not going at all.” “That is impossible.” “Do so, then; it will be a wiser plan than the first which you proposed.”” source