There is in love a strong mixture of humanity, generosity, kindness, friendship, esteem
 Adam Smith, The Theory of Moral Sentiments (1759). copy citation

Context

“and though its consequences are often fatal and dreadful, its intentions are seldom mischievous. And then, though there is little propriety in the passion itself, there is a good deal in some of those which always accompany it. There is in love a strong mixture of humanity, generosity, kindness, friendship, esteem; passions with which, of all others, for reasons which shall be explained immediately, we have the greatest propensity to sympathize, even notwithstanding we are sensible that they are, in some measure, excessive.” source