The Metaphysical Elements of Ethics by Immanuel Kant Chapter 7 Page 5

men of promoting their natural ends, which are recognized as such by all men (making their happiness his own), we might call it the sweet merit, the consciousness of which creates a moral enjoyment in which men are by sympathy inclined to revel; whereas the bitter merit of promoting the true welfare of other men, even though they should not recognize it as such (in the case of the unthankful and ungrateful), has commonly no such reaction, but only produces a satisfaction with one's self, although in the latter case this would be even greater.