One who either knows or believes that he is under no legal obligation to confer a certain benefit upon another and that he will acquire no right thereby, but nevertheless confers the benefit, cannot justly claim restitution upon the theory of misreliance :

National Life Insurance Company v. Jones, 1873, 1 Thomp. & C. (N. Y. Sup. Ct.) 466; aff. 59 N. Y. 649: Action to recover money paid by the company upon a policy of insurance. The grounds upon which recovery was sought were that the policy had been obtained by fraudulent representations and warranties. It appeared, however, that the officer of the company believed, at the time of payment, that the policy had been obtained by fraud, and paid the claim, "in part, because of the evil effect which a resistance of the claim would have upon the reputation of the company in the event of an unsuccessful resistance; also from some expected benefit, which, in some general way, might result to the company from prompt payment." Talcott, J. (p. 472): "The plaintiff believing that a good defense existed to the demand might be unwilling to encounter the risk of undertaking to prove it, might doubt whether it could be proved with sufficient clearness to secure a verdict, and for that reason have concluded that it was better to pay than to encounter a litigation which might prove unsuccessful. In such case a payment is not made under a mistake of fact, but upon the ground that, notwithstanding the fact, it is for the interest of the party paying to make the payment. So, too, the finding that the payment was made not in reliance upon a false belief as to the facts, but from other motives, inclining the plaintiff to the belief that it was for its interest to assume the false state of facts to be true, and pay without further question or inquiry is a sufficient ground for sustaining the decision. If the payment be not solely in reliance upon a falsely assumed state of facts, but from mixed motives, so that the payer, while not believing the assumed state of facts, voluntarily waives all investigation or inquiry in view of, and influenced by other motives to the payment, he has not paid on the faith of a false state of facts, and thereby influenced to the payment, but upon other considerations."

Windbiel v. Carroll, 1878, 16 Hun (N. Y. Sup. Ct.) 101: Action to recover money paid on a mortgage, upon the ground that it was an overpayment. Learned, P.J. (p. 103): " Ignorance of a fact is one thing; ignorance of the means of proving a fact is another. When money voluntarily paid is recovered back, it is because there was a mistake as to some fact. But here the plaintiff was not mistaken as to the fact. Only at the time he did not know how to prove it. The subsequent discovery of evidence to prove a fact, known to the party when he makes the payment, cannot authorize a recovery back of the money. Such a principle would be most dangerous."1

In Tennessee, however, it has been held that nothing short of knowledge or "moral certainty" will negative misreliance:

Guild v. Baldridge, 1852, 2 Swan (32 Tenn.) 294: Action to recover money alleged to have been paid under a mistake of fact. The plaintiff purchased logs from one Manning for which he in part paid Manning and took his receipt. Some years later a constable had in his hands executions against Mailing, the proceeds of which were to be paid over to the defendant. Manning had promised the constable to let the plaintiff have some logs to discharge the executions, so the constable called upon the plaintiff and requested payment. On two occasions the plaintiff told the constable that he thought he had paid Manning, and finally in the presence of the defendant the plaintiff said that "he believed he had paid the debt, but that he had nothing to show payment; and as Manning was dead he would have no bad feelings about it, and rather than have them he would pay it again." The trial court instructed the jury that "if the plaintiff, believing that he had paid the debt to Manning but choosing to pay it again rather than be supposed to withhold it, paid the money to the defendant, as the creditor of Manning, without any understanding with the defendant that the money should be refunded in any event, then the plaintiff would not be entitled to recover." But this instruction was held improper by the Supreme Court, which declared (McKinney, J., writing the opinion, p. 302) that a recovery could not be resisted "on the ground that the plaintiff, at the time of payment, may have entertained and expressed a vague belief, resting on no evidence and amounting to nothing like conviction or moral certainty, that he had previously paid the debt. The authorities cited require that he shall have had knowledge of the facts, and that term must be used in its ordinary sense."

1 See also Stokes v. Lewis, 1785, 1 Term R. 20; Holt v. Thomas, 1894, 105 Cal. 273; 38 Pac. 891; Citizens' Bank v. Rudisill, 1908, 4 Ga. App. 37; 60 S. E. 818; Frambers v. Risk, 1877, 2 111. App. 499, 504; Mowatt v. Wright, 1828, 1 Wend. (N. Y.) 355; 19 Am. Dec. 508. But see Bond v. Hays, 1815, 12 Mass. 34.