Melville Fuller

“ In order to guard the public against losses and injuries arising from the fraud or mistake or rashness or indiscretion of their agents, the rule requires of all persons dealing with public officers the duty of inquiry as to their power and authority to bind the government; and persons so dealing must necessarily be held to a recognition of the fact that government agents are bound to fairness and good faith as between themselves and their principal. ”

“ But, where the action is in special assumpsit, the express promise of the defendant fixes the measure of damages to which the plaintiff is entitled. And while the general rule is that the performance of every contract may be resisted on the ground of fraud, at law as well as in equity, yet upon a contract of sale the defendant, having accepted performance, cannot interpose this defense to defeat the contract, unless he returns the article, or proves it to have been entirely worthless, though he may ordinarily recoup the damages which he can show he has sustained through the fraud. ”

“ Where there is a written contract, and a like misunderstanding is developed, a court of equity will refuse to execute it. If a contract be unreasonable and unconscionable, but not void for fraud, a court of law will give to the party who sues for its breach damages, not according to its letter, but only such as he is equitably entitled to. ”