dissenting.
The majority seemingly demonstrates a proclivity for invading the province of the jury. The existence of a contract and the interpretation of contractual terms are matters which should be determined by the trier of fact rather than by the court via summary judgment. Johnson v. Allied Stores Corp., 106 Idaho 363, 679 P.2d 640 (1984); Bischoff v. Quong-Watkins Properties, 113 Idaho 826, 748 P.2d 410 (Ct.App.1987). This is particularly true where, as in this case, the trier of fact was to have been a jury. See Riverside Dev. Co. v. Ritchie, 103 Idaho 515, 519, 650 P.2d 657, 661 (1982); Riggs v. Colis, 107 Idaho 1028, 1030, 695 P.2d 413, 415 (Ct.App.1985). The questions of whether the contract contained a condition precedent and, if it did, whether the terms of that condition were fulfilled, are by definition questions concerning contractual terms. They should therefore have been resolved by trial, not by summary judgment.
Because the majority’s determination that the trial court was correct in denying Black Canyon leave to amend its complaint is premised upon its erroneous holding that there was no valid contract, that determina*179tion, too, is in error. Pursuant to I.R.C.P. 15(c), Black Canyon petitioned the trial court to allow it to amend its complaint by adding tort claims which had allegedly arisen out of the same transaction as the contract claims asserted in the original complaint. The majority asserts that it “must evaluate the alleged tort claims [and the propriety of the trial court’s refusal to allow the same] in light of the fact that no valid contract to lend money existed.” At 175, 176, 804 P.2d at 904, 905 (1991). However, if the issue of the existence of the contract had been properly allowed to go to trial, such an evaluation would not be taking place, and other general principles concerning the appropriate use of Rule 15(c) should have applied. These principles dictate that leave to amend a complaint to state a cause of action which would otherwise be barred by a statute of limitations will be freely granted. The amendment will relate back to the filing date of the original complaint, provided only that both the complaint and the amendment derive from the same conduct, transaction, or occurrence. Suitts v. First Sec. Bank of Idaho, N.A., 110 Idaho 15, 23, 713 P.2d 1374, 1382 (1985); Wing v. Martin, 107 Idaho 267, 270, 688 P.2d 1172, 1175 (1984). Accepting that “the rationale of the relation back rule is to ameliorate the effect of the statute of limitations,” 6 C. Wright & A. Miller, Federal Practice and Procedure §§ 1497, 1496 (1971), the key in such cases is to ascertain whether the opposing party has had adequate notice that the conduct, transaction, or occurrence set forth or attempted to be set forth in the original pleading could give rise to additional causes of action. Wright & Miller § 1497. See also Wing, 107 Idaho at 270, 688 P.2d at 1175. If such notice is evident, “[i]t is not unreasonable to require [the defendant] to anticipate all theories of recovery and prepare its defense accordingly.” Zagurski v. American Tobacco Co., 44 F.R.D. 440, 442-43 (Conn.1967). See also Tri-Ex Enters., Inc. v. Morgan Guar. Trust Co. of New York, 586 F.Supp. 930 (S.D.N.Y.1984) (where issues framed by the original pleading concerned a letter of credit, all parties were clearly provided with notice that all matters surrounding the letter of credit were open to question, and defendants’ counterclaim concerning the same letter would relate back to the time of original filing and would not be barred by the statute of limitations).
In the case before us, the original complaint filed by Black Canyon sufficiently set forth a chain of business dealings between Black Canyon, Campbell, and Idaho First to put Idaho First on ample notice that it was those business dealings gone awry which were the gravamen of the suit. The tort claims advanced by Black Canyon should have been allowed to relate back to the time of the filing of its original complaint. The trial court therefore abused its discretion by denying plaintiffs leave to amend on statute of limitations grounds.
Finally, it is noted that Idaho First makes the argument, which apparently is accepted by the majority, that allowing Black Canyon to amend would prejudice Idaho First and cause undue delay. The majority’s attention and Idaho First’s attention is directed to the trial court’s order dated December 12, 1986, setting this case for trial and pre-trial. That order set the cut-off date for the amendment of pleadings at ninety days before trial, or June 19, 1987, and ordered that discovery be completed no later than twenty-eight days before trial, or August 20, 1987. R., 23. Black Canyon’s motion to amend was filed well within those limits, on June 11, 1987. Idaho First’s arguments concerning delay and prejudice are therefore unpersuasive.
A proposed opinion for the Court, which for unknown reasons failed to command a majority, follows. Notwithstanding that implicit “no confidence” vote, the fact remains that it is structurally sound and supported by case precedent. Moreover, it would have resulted in a trial on the merits rather than a summary judgment of dismissal which precluded an airing of the facts and circumstances where a jury could make the singularly important assessment of witness credibility.
BISTLINE, Justice.Russell Campbell was a customer of the Emmett Branch of the Idaho First National *180Bank (Idaho First). He had sometimes obtained loans from Idaho First without any-written application. Shortly before August of 1981, Campbell consulted with the manager of Idaho First’s Emmett Branch concerning the formation and management of Black Canyon Racquetball Club. The club was incorporated in August of 1981. In the following month Campbell, acting as president of the club, borrowed substantial sums from Idaho First without any formal written application. With the knowledge of Idaho First’s officers, the loan money was used by Campbell to furnish the club.
By October of 1981, Campbell had discussed with Idaho First officers the possibility of borrowing funds to expand and remodel the club. These officers advised Campbell that Idaho First would not loan money for improvements until the club’s cash flow improved. Campbell contends that he was assured by the officers that when the club reached a membership level of 150, the club’s cash flow would be sufficient for Idaho First to loan the funds. The membership reached 150 but the bank refused to loan more money to Campbell.
Campbell argues that the deposition of Karen Kreps, an employee of Idaho First, establishes that Idaho First, through her, had previously loaned funds to Campbell on the basis of oral commitments. Kreps testified that she understood the terms of the loan would have been for the principal amount of $174,000, with an interest rate of two and three-quarters (2.75) percent over the current prime rate. The rate was to float over the term of the loan, and Kreps also testified that the loan involved a 12 year repayment period. Both Idaho First and Campbell anticipated that a possible source of financing was an SBA (Small Business Administration) guaranty to Idaho First.
Campbell filed two separate loan applications with Idaho First. Both times Idaho First determined that SBA loan requirements were not met, and the loans on this basis were not approved even though the club had in excess of 150 members in February, 1983. Idaho First continued to refuse to issue the funds. In the interim, Campbell, in anticipation of the loan’s approval, engaged contractors to remodel the club. Some of these contractors had begun remodeling while the loan was pending. Their depositions indicate that their commencement of work was predicated in part on the assurances of Karen Kreps to them that there was “no problem” with the Black Canyon loan.
Black Canyon and Campbell (Black Canyon) filed a complaint September 4, 1985, alleging several contract claims arising out of Idaho First’s failure to loan money. On June 11, 1987, Black Canyon filed a motion to amend the complaint seeking to add the tort claims of bad faith, misrepresentation, and breach of fiduciary duty. The trial court denied Black Canyon’s motion on July 24,1987, ruling that Counts V through VIII of Black Canyon’s proposed amended complaint were barred by the applicable statute of limitations, and that the proposed amendments did not relate back to the time of filing of the original complaint. An amended complaint which included only contract claims was filed by Black Canyon on August 5, 1987.
Idaho First moved for summary judgment. The trial court granted Idaho First’s motion on the ground that the alleged oral contract lacked complete and definite terms, and was therefore unenforceable.
The following issues are raised on appeal:
1. Whether the trial court abused its discretion when it denied Black Canyon’s motion to amend its complaint on the grounds that the causes of action advanced by the proposed amended complaint were time-barred?
2. Whether the trial court erred in granting summary judgment to Idaho First on Black Canyon’s contract claims?
I.
We first turn our attention to the question of whether the trial court abused its discretion when it denied Black Canyon’s motion to amend its complaint on the grounds that the causes of action advanced *181by the proposed amended complaint were time-barred. I.R.C.P. 15(c) is the operative rule here. It provides in pertinent part:
Rule 15(c). Relation back of amendments. — Whenever the claim or defense asserted in the amended pleading arose out of the conduct, transaction, or occurrence set forth or attempted to be set forth in the original pleading, the amendment relates back to the date of the original pleading.
This Court has consistently adhered to the principle that “[i]f the underlying facts or circumstances relied upon by a plaintiff may be a proper subject of relief, he ought to be afforded an opportunity to test his claim on the merits.” Foman v. Davis, 371 U.S. 178, 182, 83 S.Ct. 227, 230, 9 L.Ed.2d 222 (1962), adopted in Smith v. Great Basin Grain Co., 98 Idaho 266, 272-73, 561 P.2d 1299, 1305-06 (1977). In the context of Rule 15(c), this principle has dictated that leave to amend a complaint with a cause of action which would otherwise be barred by a statute of limitations will be freely granted, and the amendment will relate back to the filing date of the original complaint, if both the complaint and the amendment derive from the same conduct, transaction, or occurrence. Suitts v. First Sec. Bank of Idaho, N.A., 110 Idaho 15, 23, 713 P.2d 1374, 1382 (1985); Wing v. Martin, 107 Idaho 267, 270, 688 P.2d 1172, 1175 (1984). Given that “the rationale of the relation back rule is to ameliorate the effect of the statute of limitations,” 6 C. Wright & A. Miller, Federal Practice and Procedure §§ 1497, 1496 (1971), the key in such cases is to ascertain whether the opposing party has had adequate notice that the conduct, transaction, or occurrence set forth or attempted to be set forth in the original pleading could give rise to additional causes of action. Wright & Miller § 1497. See also Wing, 107 Idaho at 270, 688 P.2d at 1175. If such notice is evident, “[i]t is not unreasonable to require [the defendant] to anticipate all theories of recovery and prepare its defense accordingly.” Zagurski v. American Tobacco Co., 44 F.R.D. 440, 442-43 (Conn.1967). See also Tri-Ex Enters., Inc. v. Morgan Guar. Trust Co. of New York, 586 F.Supp. 930 (S.D.N.Y.1984) (where issues framed by the original pleading concerned a letter of credit, all parties were clearly provided with notice that all matters surrounding the letter of credit were open to question, and defendants’ counterclaim concerning the same letter would relate back to the time of original filing and would not be barred by the statute of limitations).
In the case before us, the original complaint filed by Black Canyon sufficiently set forth a chain of business dealings between Black Canyon, Campbell, and Idaho First to put Idaho First on notice that it was those business dealings gone awry which were the gravamen of the suit. The tort claims advanced by Black Canyon should have been allowed to relate back to the time of the filing of its original complaint. The trial court abused its discretion by denying plaintiffs leave to amend on statute of limitations grounds.
In so holding we are mindful of Idaho First’s arguments that by allowing Black Canyon to amend we are prejudicing Idaho First and are acquiescing in undue delay. We direct Idaho First’s attention to the trial court’s order dated December 12, 1986, setting this case for trial and pre-trial. That order set the cut-off date for the amendment of pleadings at ninety days before trial, or June 19, 1987, and ordered that discovery be completed no later than twenty-eight days before trial, or August 20, 1987. R., 23. Black Canyon’s motion to amend was filed well within those limits, on June 11, 1987. Idaho First’s arguments concerning delay and prejudice are therefore unpersuasive.
II.
We next address the question of whether the trial court erred in granting summary judgment to Idaho First on Black Canyon’s contract claims. We note at the outset the long-standing principles which guide our decisions in summary judgment cases. Pursuant to I.R.C.P. 56(c), “summary judgment is improperly granted where any genuine issue of material fact remains unresolved.” American Land Title Co. v. Isaak, 105 Idaho 600, 601, 671 P.2d 1063, 1064 (1983). When determining whether such an issue of material fact exists, we will liberally construe the facts and all rea*182sonable inferences which may be drawn therefrom in favor of the party against whom the summary judgment is sought. Ulery v. Routh, 107 Idaho 797, 693 P.2d 443 (1984).
The present case presents two issues of material fact which preclude summary judgment. The first issue is whether a contract existed at all, and if so, whether its terms were sufficiently complete and definite to permit enforcement. The general rule in contract cases, including oral contract cases, is that the existence of a contract and the interpretation of contractual terms are matters which should be determined by the trier of fact rather than by the court via summary judgment. Bischoff v. Quong-Watkins Properties, 113 Idaho 826, 828, 748 P.2d 410, 412 (Ct.App.1987); Johnson v. Allied Stores Corp., 106 Idaho 363, 679 P.2d 640 (1984). This is particularly true where the trier of fact is to be a jury. See Riverside Dev. Co. v. Ritchie, 103 Idaho 515, 519, 650 P.2d 657, 661 (1982); Riggs v. Colis, 107 Idaho 1028, 1030, 695 P.2d 413, 415 (Ct.App.1985). Black Canyon requested a jury trial. Black Canyon contends that a contract did in fact exist and that the loan amount, interest rate, and duration were settled upon with a reasonable degree of certainty. These allegations are supported by the deposition of Russell Campbell (pp. 96-99), the deposition of Karen Kreps (pp. 50-51, as to term and interest rate), and the depositions of Kenneth Johns and Glenn Morrow (the loan would be granted if the club attained a certain membership level) and inferences which can reasonably be drawn from those depositions. Summary judgment in favor of the defendant bank was therefore improperly granted.
Whether Idaho First is estopped from denying the existence of a contract is the second issue of material fact. To prevail on such a claim, Black Canyon must prove the existence of all four elements of promissory estoppel. Those elements are: (1) reliance upon a specific promise; (2) substantial economic loss to the promisee as a result of such reliance; (3) the loss to the promisee was or should have been foreseeable by the promisor; and (4) the promisee’s reliance on the promise must have been reasonable. Gilbert v. City of Caldwell, 112 Idaho 386, 391-92, 732 P.2d 355, 360-61 (Ct.App.1987); Mohr v. Shultz, 86 Idaho 531, 540, 388 P.2d 1002, 1008 (1964). Evidence pertaining to each of these elements was put forward by Black Canyon. When they were deposed, both Kenneth Johns and Glenn Morrow stated that they had relied on Karen Kreps statements to them concerning the Black Canyon loan in making their decisions to proceed with work on the club, that they had accepted promissory notes from Campbell based on Kreps’ assurances, and that Karen Kreps was aware of their reasons for requesting such information (deposition of Kenneth Johns at 6, 10; deposition of Glenn Morrow at 6-9, 33, and 36-37). Given this testimony, and the fact that Black Canyon had requested a jury trial, the resolution of the promissory estoppel issue should have been left to the trier of fact, thereby precluding summary judgment. Riverside Dev. Co. v. Ritchie, 103 Idaho 515, 518, 650 P.2d 657, 660 (1982). See also Bowen v. Westerhaus, 224 Kan. 42, 578 P.2d 1102 (1978).
The summary judgment of the district court should be reversed, and the case should be remanded with instructions to allow the plaintiffs to amend their complaint.