We are required to do this on natural principles. Nature herself,— in other words, the common feeling and common sense of mankind,— teaches us what true love is, in distinction from interested or merely selfish love. If we profess to love a person, it is the common and natural understanding in the case, that we profess to love him as he is; in other words, we love him for what he is in and of himself; and not merely or chiefly for the benefits which he may have conferred upon us. The principles of the philosophy of the mind, which are drawn chiefly from an observation of the feelings and conduct of men, do not appear to recognize any other true love than this. If my neighbor, for instance, declares that he loves me, I accept his declaration, and rejoice in it; but if I afterwards learn, that he loves me merely in consequence of some benefits I have conferred upon him, I can truly say to him, he is mistaken in the whole matter; and that he loves himself, and not me. It seems to be self-evident, that all true love must terminate in the object that is beloved; and not in the person that exercises love. And accordingly true love is never egotistical. In other words, it shows no disposition to revert continually to itself; and to revolve around its own center of origin. On the contrary, true or pure love, in distinction from that which is self-interested, is diffusive, generous, and self-forgetting. It expatriates itself, as it were; flying on its beautiful wings from its own heart to find a home in the heart of another. And it is accordingly with such love, a love which lives for another and not for itself, a love devoid of any debasing and inferior mixture, that we ought to love God.
— The Interior or Hidden Life (1844) Part 1, Chapter 12.