"Though our brother is upon the rack, as long as we ourselves 
    are at our ease, our senses will never inform us of what he 
    suffers."

   "Pity and compassion are words appropriated to signify our 
    fellow-feeling with the sorrow of others. Sympathy, though 
    its meaning was, perhaps, originally the same, may now, 
    however, without much impropriety, be made use of to denote 
    our fellow-feeling with any passion whatever."

   "Sympathy, therefore, does not arise so much from the view of 
    the passion, as from that of the situation which excites it. 
    We sometimes feel for another, a passion of which he himself 
    seems to be altogether incapable; because, when we put 
    ourselves in his case, that passion arises in our breast from
    the imagination, though it does not in his from the reality. 
    We blush for the impudence and rudeness of another, though he
    himself appears to have no sense of the impropriety of his 
    own behaviour..."

    -Adam Smith (1723-1790), The Theory of Moral Sentiments (1759)