“Man has almost constant occasion for the help of his brethren, and it is vain for him to expect it from their benevolence only.He will be more likely to prevail if he can interest their self-love in his favor, and show them that it is for their own advantage to do for him what he requires of them...It is not from the benevolence of the butcher, the brewer, or the baker that we expect our dinner, but from their regard to their own interest....