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.
Waiver is a necessary correlative of election. Election is the choice between two inconsistent rights. Election of one of such rights is a waiver of the other. Accordingly if the party not in default has the right of election between treating breach by the party in default as a discharge of the contract, or treating the contract as in full force and effect, he may, if he choose, take the latter alternative. Such election waives Lis right to treat the contract as discharged.1 Thus, if the vendor breaks the contract and the vendee insists on his continuing the performance, the vendee cannot subsequently elect to treat such breach as a discharge.2 So if an employe for an indefinite period is laid off for a month without pay, and he acquiesces therein and treats the contract as in force, he cannot subsequently treat such breach as a discharge and recover on quantum meruit.3 If, the party not in default has elected after breach to treat the contract as still in effect, subsequent impossibility which would have discharged the contract had there been no breach, will discharge it since the breach is waived.4 While such waiver prevents the party not in default from subsequently treating the contract as ended, it does not prevent him from recovering damages for defective performance where no other ground of discharge exists,5 unless he has by his conduct induced the adversary party to make such defective performance by causing him to believe that such performance will be accepted in full discharge of his liability. No consideration for a waiver of breach as discharge is necessary.6
1 McGowan v. United States, 35 Ct. CI. 606; McConnell v. Hewes, 50 W. Va. 33; 40 S. E. 436. For purposes of a mechanic's lien Grace v. Building Association, 166 111. 637; 46 N. E. 1102; reversing 63 111. App. 339.
2 Hunnicutt, etc., Co. v. Van Hoose, 111 Ga. 518; 36 S. E. 669.
3 Clark v. Collier, 100 Cal. 256; 34 Pac. 677.
4 Crawford v. McKinney, 165 Pa. St. 609; 30 Atl. 1047.
1 Sorette v. Development Co., 31 N. S. 427; District of Columbia v. Iron Works, 181 U. S. 453; Witmer Brothers Co. v. Weid, 108 Cal. 569; 41 Pac. 491; Pitcher v. Lowe, 95 Ga. 423; 22 S. E. 678; Dahl v. Thompson, 98 la. 599; 67 N. W. 579; Jones v. Brown, 171 Mass. 318; 50 N. E. 648; Pvobinson v. Ry., 103 Mich. 607; 61 N. W. 1014; Klein v. Buck. 73 Miss. 133; 18 So. 891; Izard v. Kimmel, 26 Neh. 51; 41 N. W. 1068; Plummer v. Kelly, 7