"The theory of Moral Sentiments: by Adam Smith,1759

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The origin of moral sentiments is sympathy,
placing oneself imaginatively in the situation of another in order to realize the passions which affected him.
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We approve the passions of another and regard them as suitable if,imagining ourselves in like circumstances,we find that we would have similar feelings.
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The amiable virtues of condescension and indulgence stem from sympathy ;
and the respectable virtues of self-denial and self-command arise in those who are the objects of sympathy.
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The unsocial passions,hatred and resentment,are disagreeable ;
the social passions such as generosity,kindness,compassion,are agreeable ;
and the selfish passions are mixed,neither as disagreeable as the unsocial passions nor as agreeable as the social.
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The propriety of an action is the fitness of its motivating feeling to the cause of that feeling ;
the merit or demerit of an action rests upon the character of the consequences of the action.
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Con science is the faculty of judgment of the man within the breast,the inward man who knows the actual motivations of his actions.
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