(dissenting).
Having reached a different view of the facts and applicable law, I respectfully dissent.
I. While the majority cites and apparently relies on our rule we give weight to fact-findings of trial court but are not bound by them, rule 14(f)(7), Rules of Appellate Procedure, the first prong of the rule is of questionable applicability in this case. Trial court’s concept of the facts seems to have been derived initially from an “Informal Trial Brief” filed by plaintiff. Thereafter, the court occasionally took the position only legal and not factual issues were involved.
As defense counsel sought to cross-examine plaintiff the following colloquy occurred:
“THE COURT: Mr. Kober, I don’t want to limit your cross-examination, but I said at the outset of this hearing I thought this was strictly a legal argument. You are trying to make it into a jury case, and I don’t know where you are headed. * * *”
At a later point the court observed to defense counsel, “I think the Court has to decide this as a legal argument rather than a fact question. You are just opening up a can of worms as far as I’m concerned.”
Nonetheless, trial court’s finding of facts included the finding plaintiff “was told in forceful terms by Mr. Van Lengen that they wanted no part of his visits in the future, and that they did not expect any support and they would support Michael.” The court further found plaintiff relied on “the representations of the Defendant and her later acquired spouse.”
On direct examination plaintiff was asked what Mr. Van Lengen said to him. When defense counsel objected on hearsay grounds the court ruled:
“THE COURT: If he was her husband, Mr. Kober, he apparently was acting as her agent, and by and for her. I am going to let that in. Ordinarily the Court doesn’t care much about hearsay, but if this man was her husband, he was acting for her. I am going to let it go in.
*441“MR. KOBER [defense counsel]: May it please the Court, not certain here, he may not have been her husband at that time and place—
“THE COURT: He eventually did become her husband, didn’t he?
“MR. KOBER: He wasn’t at the time. He couldn’t have been an agent.
“THE COURT: You are arguing over semantics, Mr. Kober. He may go ahead and answer.”
As the majority opinion indicates, Mr. Van Lengen was not in attendance at trial. There is no indication in the record defendant had any forewarning alleged statements of Mr. Van Lengen not made in defendant’s presence would be injected into plaintiff’s case. When defendant sought to deny Van Lengen had made the statements attributed to him, the court objected, “Wait a minute. Now you are not — you are going — saying what somebody else said. You don’t know whether John [Van Lengen] told him that; you weren’t there, were you?”
Of course, married women in Iowa have had the same right as husbands to manage their own property for at least 100 years. See § 597.1, The Code, 1977; § 2202, The Code, 1873; Note, 25 Iowa L.Rev. 351, 353-354 (1940). Marriage does not install a husband as agent to bargain away his wife’s property. Snyder v. Abel, 235 Iowa 724, 730, 17 N.W.2d 401, 404 (1945); Fulton Bank v. Mathers, 183 Iowa 226, 230-231, 166 N.W. 1050, 1051 (1918). Equally ineffective for this purpose is a pending marriage, as in this case.
Our de novo review in this equity matter should proceed without attributing weight to the findings below.
II. Plaintiff’s action is based solely on the pleaded theory “[t]hat Defendant is equitably estopped from enforcement of said judgment for support * * *Plaintiff further affirmatively pleaded “[t]hat the child support provision set forth in said Decree constitutes a judgment against Plaintiff, and apparently creates a lien encumbering said real estate * * *
As plaintiff relies on equitable estoppel, certain rules apply.
Equitable estoppel is applied to prevent fraud and injustice and exists wherever a party cannot in good conscience gainsay his or her own acts or assertions. Dart v. Thompson, 261 Iowa 237, 243, 154 N.W.2d 82, 86 (1967). The doctrine is applied where, because of something a party has done or omitted to do, he or she is denied the right to plead or prove an otherwise important fact. Anfenson v. Banks, 180 Iowa 1066, 1092-1094, 163 N.W. 608, 616 (1917). The rule functions to prevent fraud, actual or constructive. Id.
Equitable estoppel always operates as a shield, never as a sword. D. Dobbs, Remedies, § 2.3 at 42 (1973); 28 Am.Jur.2d, Estoppel and Waiver, § 33, p. 637 (1966). The burden to prove estoppel is on the party asserting it. Each element must be proved clearly, convincingly and satisfactorily. Colthurst v. Colthurst, 265 N.W.2d 590, 598 (Iowa 1978); Pillsbury Co. v. Ward, 250 N.W.2d 35, 39 (Iowa 1977); Manson State Bank v. Diamond, 227 N.W.2d 195, 201 (Iowa 1975); Davenport Osteopathic Hosp. Ass’n v. Hospital Serv., 261 Iowa 247, 256-257, 154 N.W.2d 153, 159 (1967); Smith v. Coutant, 232 Iowa 887, 890-893, 6 N.W.2d 421, 424-425 (1942).
Here the doctrine is asserted affirmatively to strip defendant of installment judgments which are alleged to be valid and constitute a lien on plaintiff’s real estate. In this connection it should be noted equitable estoppel by acquiescence historically evolved to deprive a party from obtaining distinctive equitable remedies to which he or she would otherwise be entitled, not to cut off remedies at law or statutory rights. J. Pomeroy, Equity Jurisprudence, § 817, pp. 245-246 (Symons 5th ed. 1941); see Thodos v. Shirk, 248 Iowa 172, 185-187, 79 N.W.2d 733, 740-741 (1956); cf. Smith v. City of Jefferson, 161 Iowa 245, 249, 142 N.W. 220, 221-222 (1913).
It also should be observed plaintiff is not relying on the statute of limitations, which is nowhere asserted in this ease. We said in *442Cullinan v. Cullinan, 226 N.W.2d 33, 35 (Iowa 1975), “[e]ach installment is in itself a judgment as it becomes due. The principle is now codified in § 598.22, The Code.” The statute apparently runs from the time each installment falls due. See Bennett v. Tomlinson, 206 Iowa 1075, 1079, 221 N.W. 837, 840 (1928); Annot., Alimony or Support Order—Action—Time, 70 A.L.R.2d 1250, § 4(b), pp. 1258-1262 (1960). Certainly installments not due were uncollectable. Future installments were subject to modification at any time. It seems illogical, then, to speak of defendant’s delay in collection proceedings in terms of a time period originating with the dissolution decree. If defendant slept on her rights the date of each installment should be fixed as the date upon which the slumber commenced. Cf. Smith v. Smith, 168 Ohio St. 447, 451, 156 N.E.2d 113, 117 (1959).
The majority opinion first intimates that an “estoppel by acquiescence” resulted in a “waiver” and therefore, unlike the laches doctrine, does not require a determination whether the person asserting it was harmed or materially prejudiced. At a later point in the opinion the majority nonetheless intimates plaintiff was prejudiced because he remarried, fathered four more children, and took title to real estate.
III. This dissent first addresses the question whether equitable “estoppel by acquiescence” requires the element of harm or prejudice to the person asserting it. We so held in Cullinan v. Cullinan, supra, 226 N.W.2d at 36. That conclusion found ample support in authorities which state a necessary element of equitable estoppel requires the person asserting it to prove he or she incurred injury or prejudice, or the other party obtained benefits.
“Equitable estoppel rests largely upon injury or prejudice to the rights of him who asserts it, and it is said in this respect that it is the natural effect upon the party claiming an estoppel that gives it vitality. Broadly speaking, injury, detriment, or prejudice to the party claiming the estoppel is one of the essential elements of an equitable estoppel, or estop-pel in pais. Since the function and purpose of the doctrine of estoppel are the prevention of fraud and injustice, there can be no estoppel where there is no loss, injury, damage, detriment, or prejudice to the party claiming it. Moreover, the injury or prejudice involved must be actual and material or substantial, and not merely technical or formal. * * *
“The rule that estoppel arises only where there is prejudice or the like applies whether the estoppel is based upon words, conduct, silence, delay, negligence, or acceptance of benefits.” —28 Am.Jur.2d, Estoppel and Waiver, § 78, pp. 715-716
See also Manson State Bank v. Diamond, supra, 227 N.W.2d at 201; State v. Raymond, 254 Iowa 828, 836, 119 N.W.2d 135, 140 (1963); Goodwin Tile & Brick Co. v. DeVries, 234 Iowa 566, 568, 13 N.W.2d 310, 312 (1944); Smith v. Coutant, supra, 232 Iowa at 892, 6 N.W.2d at 424.
Majority seeks to modify Cullinan by analyzing and relying on Anthony v. Anthony, 204 N.W.2d 829, 834 (Iowa 1973). We there quoted language from Humboldt Livestock Auction, Inc. v. B&H Cattle Co., 261 Iowa 419, 432, 155 N.W.2d 478, 487 (1967), which concerned only the knowledge element of “acquiescence.” In turn, the Humboldt opinion quoted only from Olson v. Clark, 252 Iowa 1133, 1138, 109 N.W.2d 441, 444 (1961). The Olson opinion’s reference to “acquiescence” cited only to Atkins v. Reagan, 244 Iowa 1387, 1390, 60 N.W.2d 790, 791 (1953). But both Olson and Atkins concerned “acquiescence” only in a very narrow and esoteric sense: where adjoining landowners occupy their respective premises to a certain line which they know is not the true one but which they mutually recognize as the dividing point for ten years, that line shall be established as a boundary. The doctrine dictates under those circumstances consent may be inferred from silence; in short, an owner may infer the other owner with knowledge the line is not the true one, has “waived or abandoned his right.” The ten-year period is statutory.. § 650.14, The Code.
*443The majority cites two Iowa decisions in addition to Anthony for its theory equitable estoppel by acquiescence in this jurisdiction does not require the detriment-or-benefit element, and therefore the Cullinan language, 226 N.W.2d at 36, imposing this requirement referred only to laches, not es-toppel by acquiescence.
The first authority cited is Olson v. Clark, supra, which, as above noted, involved an acquiescence rule of real property applicable only to boundary lines and now statutorily embedded in our law.
The second case is Carlson v. Smith, 213 Iowa 231, 236 N.W. 387 (1931). There an elderly person about to travel to Sweden was persuaded by a foster daughter to deed her his farm with the agreement she was to return the instrument if he came back safely. When the grantor came back defendant refused to return the deed. An action in equity was instituted to set aside the conveyance. Both the grantor and his attorney testified to the arrangement, made in the lawyer’s office. Defendant grantee claimed she did not agree to the plan as outlined by the grantor and his attorney, but merely remained silent. This court held: .
“A court of equity will not lend its countenance to an evasion of the effect of a transaction of this character on the ground that one sitting by with full knowledge of the understanding of the opposite party, and accepting the delivery of the deed with such understanding, did not acquiesce therein because of mere silence.” — 213 Iowa at 237, 236 N.W. at 389
A constructive trust was imposed. It is plain the court’s action was based on fraud which if successful would have resulted in injury to the person asserting the acquiescence doctrine as well as benefit to the party guilty of fraud.
Neither of the above cases lend support to the concept for which they are cited.
Our application of equitable estoppel by acquiescence in Anthony, supra, 204 N.W.2d at 834, rested not only on reliance by defendant father, but on the unconscionable vindictiveness of the mother who sought to collect child support only when the daughter reestablished contact with defendant. There the plaintiff mother had executed a written release of “any lien existing” against defendant’s property by virtue of the divorce decree. Anthony followed the usual rule that the doctrine of equitable estoppel by acquiescence ordinarily is applied to transactions in which it would be unconscionable to permit a person to maintain a position inconsistent with one in which he or she has acquiesced. 28 Am.Jur.2d, Estoppel and Waiver, § 57, p. 673. It is difficult to conceive an “unconscionable” situation in which the other party has not relied on the asserted acquiescence to his or her injury or prejudice, or the party against whom the doctrine is asserted has not obtained an unfair advantage.
The rules applicable with respect to the type of estoppel in issue here were distilled thoroughly in Anfenson v. Banks, supra, where plaintiffs who lost money in a bank failure sought to hold defendant liable as a partner on the theory he publicly did not deny or repudiate unauthorized publications he was a partner:
(1) “[Wjhen the party is sought to be charged simply because he was silent, or because he has done nothing * * * the party claiming the es-toppel assumes a * * * difficult burden,” 180 Iowa 1095, 163 N.W. at 617;
(2) “[a] party setting up an estoppel by conduct is bound to the exercise of good faith and due diligence to know the truth,” 180 Iowa at 1106, 163 N.W. at 620; and,
(3) it must clearly appear “that, by his * * * silence when as an honest man, he ought to have spoken, he has misled another to his injury, or has himself thereby acquired an unfair advantage,” 180 Iowa at 1091, 163 N.W. at 616.
Clearly, our adjudicated cases hold the party attempting to assert equitable estop-pel must have relied to his or her prejudice, or the party against whom it is asserted must have obtained an unfair advantage.
*444IV. Majority logically cannot assert defendant is estopped by virtue of any alleged statements made by her. To do so would be to rely on the alleged agreement of the type we held in Anthony violates public policy. Parenthetically, it should be noted defendant denied those alleged statements and plaintiff conceded he continued to make payments following the date he claims the conversation occurred.
The circumstances of this case therefore should be examined to determine whether plaintiff justifiably relied on defendant’s failure to force him to pay what he owed her.
The majority finds plaintiff relied by ceasing to make child visitations, remarrying, fathering four more children, and taking title to real estate.
It is significant that plaintiff did not testify he relied on defendant’s inaction (acquiescence) in any of these matters. He sought to show the alleged agreement above referred to, a pact we held in Anthony, supra, 204 N.W.2d at 834, to be “invalid for any purpose.” Enforcement of such alleged agreements through the equitable estoppel doctrine only would frustrate the salutary rule of Anthony in every such situation.
Plaintiff promptly remarried. He was remarried when the alleged conversation with Van Lengen occurred. He never asserted he relied on any act or inaction of defendant in pursuing this course. Nor could he reasonably assert he was prejudiced by his remarriage, or becoming the father of four more children.
Much less could plaintiff assert reliance and resulting prejudice because he invested in real estate the money he should have used to pay child support. He came to live in a $50,000 home in which he had $32,000 equity. He now would resist paying the judgment installments with cheap dollars.
Plaintiff has shown neither reliance nor prejudice. He has failed to prove clearly, convincingly and satisfactorily each element necessary to invoke equitable estoppel by acquiescence.
I would reverse with directions to enter judgment for the defendant.
UHLENHOPP, HARRIS and McCOR-MICK, JJ., join in this dissent.