This section is from the book "The Law Of Contracts", by William Herbert Page. Also available from Amazon: Commercial Contracts: A Practical Guide to Deals, Contracts, Agreements and Promises.
If the party against whom relief is sought concedes that the contract has taken effect, but seeks to add a condition thereto by extrinsic evidence, he is seeking to add to a written contract by extrinsic evidence of the intention of the parties direct. If the contract is complete and is therefore one within the parol evidence rule, such evidence is inadmissible.1 The acceptor of a bill of exchange cannot show that the acceptance was made upon an oral condition.2 But if "executor " is added to the signature of the acceptor, an oral contract that he should be liable only out of the funds of the estate has been held enforceable.3 If a promissory note is executed and delivered, extrinsic evidence is inadmissible to show a condition subsequent,4 as that it is to be void if the machinery, in payment of which it is given, does not do a specified amount of work in a specified time,5 that the note is given simply to show the amount of unsold goods in the possession of the makers of the note belonging to the payee, and that the note was not to be paid unless the goods were sold,6 or that its payment is contingent on the existence of an endowment fund;7 or that the maker of a note is to have an option of surrendering the policy for which the note was given, taking out another policy at a lower rate, and having the note canceled;8 or that it is not to be paid if the maker of another note for which this is given should become bankrupt.9 A executed a note payable to B, a business college, and B executed a certificate that A had purchased a scholarship which in terms was assignable and would enter college at a specified date. It was held by a divided court that an oral contract that such note should not be paid if the maker did not attend and could not sell the scholarship could not be shown to defeat recovery upon such note.10 So a bond to secure an agent's performance of duty can not be shown to be upon oral condition that the obligee of the bond should give immediate notice of the surety of any default by the agent.11 So a written contract for the sale of hops, cannot be avoided by showing an oral agreement that there should be no sale if the market was not as represented by the vendor.12 So a written contract for the sale of the business, and the payment of a certain sum of money therefor, cannot be avoided by showing an oral agreement that this money should be paid only if the business was successful.13 So a written contract of sale cannot be avoided by showing a contemporaneous oral contract giving the vendee the option to cancel his order in certain contingencies.14 So a contract for procuring a right of way for a railroad cannot be avoided by showing that the contract was to be defeasible if the railroad company did not bridge a certain river.15 So a written contract guaranteeing capacity of a heater cannot be shown by extrinsic evidence to be conditioned on the vendee's building a stone wall under the house where the heater was to be used.16 So a written contract of guaranty cannot be shown to be defeasible if mortgage security for the debt were given.17 So if a grantee assumes a mortgage debt in the deed to him, he cannot show that this was conditioned on the payment of a certain sum by the grantor to the grantee.18 In all these cases the condition is nothing more than an oral term sought to be incorporated in a complete written contract, or invoked to contradict that part of the contract which has been reduced to writing. It is clearly unenforceable under the parol evidence rule.
24 Adams v. Morgan, 150 Mass. 143; 22 N. E. 708.
1 Levy, etc., Co. v. Kauffman, 114 Fed. 170; 52 C. C. A. 126; Mackey v. Magnon, 28 Colo. 100; 62 Pac. 945; affirming 54 Pac. 907; Bass Dry Goods Co. v. Mfg. Co., 119 Ga. 124; 45 S. E. 980; Stapleton v. Mun-roe, 111 Ga. 848; 36 S. E. 428; Mc-Cormick Harvesting Machine Co. v. Markert, 107 la. 340; 78 N. W. 33; Gathright v. Improvement Co. (Ky.), 56 S. W. 163; Feld v. Stewart, 78 Miss. 187; 28 So. 819; Trip-lett v. Woodward's Admr., 98 Va. 187; 35 S. E. 455: Hyde v. Bank, 115 Wis. 170; 91 X. W. 230.
2 Burns, etc., Co. v. Doyle. 71 Conn. 742; 71 Am. St. Rep. 235; 43 Atl. 483.
3Sehmittler v. Simon, 114 N. Y. 176; 11 Am. St. Rep. 621; 21 N. E. 162.
4 Aultman v. Hawk (Neb.), 95 N. W. 695.
5Lunsford v. Malsby, 101 Ga. 39; 28 S. E. 496.
6 Western Mfg. Co. v. Rogers. 54 Neb. 456: 74 X. W. 849. But while inadmissible as a defense, such a contract has been held available for a counter-claim, as a collateral con tract. Clement Bane & Co. v. Houck, 113 la. 504: 85 X. W. 765.
7 Trustees of Christian University v. Hoffman, 95 Mo. App. 488; 69 S. W. 474.
8Middleton v. Griffith, 57 N. J. L. 442; 51 Am. St. Rep. 617; 31 Atl. 405.
9 Central Savings Bank v. O'Connor, - Mich. -; 94 N. W. 11.
10 Jamestown Business College Association v. Allen, 172 N. Y. 291; 92 Am. St. Rep. 741; 64 N. E. 952.
11 Mason, etc., Co. v. Gage, 119 Mich. 361; 78 N. W. 130.
12 Lilienthal v. Brewing Co., 154 Mass. 185; 26 Am. St. Rep. 234; 12 L. R. A. 821; 28 N. E. 151.
13 Van Arsdale v. Brown, 18 Ohio C. C. 52; 9 Ohio C. D. 488.
14Houck v. Wright (Miss.), 23 So. 422; Hanrahan v. Association, 66 N. J. L. 80; s. c, 67 N. J. L. 526; s. c, 68 N. J. L. 730; 48 Atl. 517.