Immanuel Kant Quote
Beneficence is a duty. He who often practices this, and sees his beneficent purpose succeed, comes at last really to love him whom he has benefited. When, therefore, it is said, "Thou shalt love thy neighbor as thyself," this does not mean, "Thou shalt first of all love, and by means of love (in the next place) do him good"; but: "Do good to thy neighbour, and this beneficence will produce in thee the love of men (as a settled habit of inclination to beneficence)."
Metaphysical Elements of Ethics (1780). Translated by Thomas Kingsmill Abbott, translation available at Philosophy.eserver.org. From section "Preliminary Notions of the Susceptibility of the Mind for Notions of Duty Generally", Part C ("Of love to men")