“ The general indignation of other people, against the baseness of their ingratitude, will even, sometimes, increase the general sense of his merit. No benevolent man ever lost altogether the fruits of his benevolence. ”
 Adam Smith, The Theory of Moral Sentiments (1759). copy citation

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“Nature, which formed men for that mutal kindness, so necessary for their happiness, renders every man the peculiar object of kindness, to the persons to whom he himself has been kind. Though their gratitude should not always correspond to his beneficence, yet the sense of his merit, the sympathetic gratitude of the impartial spectator, will always correspond to it. The general indignation of other people, against the baseness of their ingratitude, will even, sometimes, increase the general sense of his merit. No benevolent man ever lost altogether the fruits of his benevolence. If he does not always gather them from the persons from whom he ought to have gathered them, he seldom fails to gather them, and with a tenfold increase, from other people. Kindness is the parent of kindness; and if to be beloved by our brethren be the great object of our ambition, the surest way of obtaining it is, by our conduct to show that we really love them.
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