An estoppel in pais, or an estoppel in fact, is one which does not spring from a record, or from a deed; but is made to appear to the jury by competent evidence. While the former modes of estoppel have declined in importance, and have been restrained within narrower limits than of old, estoppel in pais has been greatly extended, and is found to be usefully applicable to a great variety of cases.1 Estoppel by deed or record is sometimes called technical estoppel, and estoppel in pais is called equitable estoppel. From the course of recent adjudication it would seem that courts are inclined rather to restrict technical estoppel, and to favor the remedy or defence of equitable estoppel.

Originally it was applied, almost exclusively, to those acts which were almost, or for some purposes quite, the equivalent of deed or record; as a feoffment, or an attornment in pais after a grant by deed of a reversion. It was, however, at an early period extended beyond those limits; and in some directions quite far. And now, a long course of adjudication, founded in part upon what may be called commercial principles, and in part upon equitable principles, seems to have established two forms of estoppel in pais. These, so far from being considered as subject to the odium which once attached to the whole law of estoppel, are grounded upon principles of the most obvious and certain reasonableness and justice. And they are freely applied in recent times, both in England and in this country, whenever it is thought that they would aid in the enforcement of right or in the prevention of wrong.

(oo) Stevens v. Benton, 1 Duvall, 112. See on this subject of estoppels by deed, Carpenter v. Simmons, 1 Rob. 360; Saco v. Casanueva, 30 Cal. 560; Edwards v.

State, etc. 22 Ark. 303; Shroyer v. Richmond, 16 Ohio, 455.

(op) Rhine v. Ellen, 36 Cal. 362.

(oq) Smith v. Lock, 18 Mich. 56.

1 For ordinary definitions of estoppels in pais, see Carr v. London, etc R. Co. L. R. 10 C. P. 307.

The first of these principles is that which relates to, and is perhaps confined to, negotiable paper. This, the law-merchant recognizes (as has been said in a former chapter) as, for many purposes and in many respects, the equivalent of money; and seeks to make it an adequate equivalent. The rule, that the consideration of negotiable paper cannot be inquired into, excepting as between immediate parties, is founded upon this principle of estoppel; that is, upon the principle, that a party who has for his own benefit, and in his own business, made use of negotiable paper, as money, is estopped from taking this character away from it, by showing the absence of one thing * that might be essential to the validity of the contract, by which the paper is to be replaced by money. Other rules in relation to this subject rest upon the same foundation; as that which prohibits the acceptor, or indorser, from impeaching, by proof of forgery or other inherent defect, the paper which, bearing his name by his own act, has passed as money into the hands of an innocent party by fair negotiation. We only mention these things here, and, without further discussion, refer to our chapter on Indorsement, in our first volume, for a more detailed statement of the rules, and of the applications of them.

The other class of estoppels in pais is of a different, and yet an analogous character. In them the rule rests upon what may seem to be but a broader assertion of the same principle. It is, that no man shall found a right upon his own wrong; or, in other words, that whatever a man has said, or implied, wrongfully, for his own advantage, (p) that he shall be bound by, when it may turn to his disadvantage, however false it may be in fact. We would state the rule thus. When a man has made a declaration or a representation, or caused, or, in some cases not prevented, a false impression, or done some significant act, with intent that others should rely and act thereon, and upon which others have honestly relied and acted, he shall not be permitted to prove that the representation was false, or the act unauthorized or ineffectual, if injury would occur to the innocent party who had acted in full faith in its truth or validity. (q)l For that which would otherwise be only a matter * of evidence, becomes, in such a case, and by force of law, matter of estoppel, and a bar to all question. A very extended * application is now made of this rule, and a great variety of subordinate and subsidiary principles may be drawn from the numerous cases in which this application is made; and among them one of frequent recognition, - qui tacet consentire videtur, by force of which an estoppel by silence is not unfrequent. The necessity of economizing space compels us to refer, for them, to the notes, in which we present some of the many illustrations of this rule, which modern adjudication supplies. (r)1

(p) Jewett v. Miller, 10 N. Y. (6 Seld.) 402. See also Green v. Green, 16 La. An. 39, where it was held, that the reputed father, who has introduced the mother as his wife, and the child as his son, will not be permitted afterwards to bastardize it, to resist a claim to property.

(q) Greaves v. Key, 3 B. & Ad. 313; Heane v. Rogers, 9B.&C. 577. In Pickaid v. Sears, 6 A. & E. 469, per Denman, C. J.: "The rule of law is clear, that, where one by his words or conduct wilfully causes another to believe the existence of a certain state of things, and induces him to act on that belief, so as to alter his own previous position, the former is concluded from averring against the latter a different state of things as existing at the same time." Gregg v. Wells, 10 A. & E. 90; Downs v. Cooper, 2 Q. B. 256. Parke, B., in Freeman v. Cooke, 2 Exch. 654, 663, declares "by the term 'wilfully,' however, in that rule, we must understand, if not that the party represents that to be true which he knows to be untrue, at least that he means his representation to be acted upon, and that it is acted upon accordingly; and if, whatever a man's real intention may be, he so conducts himself that a reasonable man would take the representations to be true, and believe that it was meant he should act upon it, and did act upon it as true, the party making the representation would be equally precluded from contesting its truth; and conduct, by negligence or omission, where there is a duty cast upon a person, by usage of trade or otherwise, to disclose the truth, may often have the same effect." And in Hawes v. Marchant, 1 Curtis, 136, per Curtis, J.: "To constitute an estoppel in pais, a party must have designedly made an admission inconsistent with the defence or claim which he proposes to set up, and with his knowledge and consent another party must have so acted on that admission that he will be injured by allowing the admission to be disproved; and this injury must be coextensive with the estoppel." Smith v. Schroeder, U. S. C. C. Rhode Island, 21 Law Rep. 739; Dyer v. Cady, 20 Conn. 563; Cambridge Savings Bank v. Littleneld, 6 Cush. 210. Both the intention to influence and the actual influence must be made out. Howard v. Hudson, 2 Ellis & B. 1; Patterson v. Lytle, 11 Penn. St. 53; Calhoun v. Richardson, 30 Conn. 210; but conduct or other facts may amount to an admission. Doe v. Groves, 10 Q. B. 486;