“When the happiness or misery of others depends in any respect upon our conduct, we dare not, as self–love might suggest to us, prefer the interest of one to that of many. The man within immediately calls to us, that we value ourselves too much and other people too little, and that, by doing so, we render ourselves the proper object of the contempt and indignation of our brethren.l Neither is this sentiment confined to men of extraordinary magnanimity and virtue. It is deeply impressed upon every tolerably good soldier, who feels that he would become the scorn of his companions, if he could be supposed capable of shrinking from danger, or of hesitating, either to expose or to throw away his life, when the good of the service required it.
One individual must never prefer himself so much even to any other individual, as to hurt or injure that other, in order to benefit himself, though the benefit to the one should be much greater than the hurt or injury to the other. The poor man must neither defraud nor steal from the rich, though the acquisition might be much more beneficial to the one than the loss could be hurtful to the other. The man within immediately calls to him, in this case too, that he is no better than his neighbour, and that by this unjust preference he renders himself the proper object of the contempt and indignation of mankind; as well as of the punishment which that contempt and indignation must naturally dispose them to inflict, for having thus violated one of those sacred rules, upon the tolerable observation of which depend the whole security and peace of human society. There is no commonly honest man who does not more dread the inward disgrace of such an action, the indelible stain which it would for ever stamp upon his own mind, than the greatest external calamity which, without any fault of his own, could possibly befal him; and who does not inwardly feel the truth of that great stoical maxim, that for one man to deprive another unjustly of any thing, or unjustly to promote his own advantage by the loss or disadvantage of another, is more contrary to nature, than death, than poverty, than pain, than all the misfortunes which can affect him, either in his body, or in his external circumstances”
(TMS, Part 3, Chapter 3, paragraphs 5 and 6: 137-8).