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.
In discussing breach and its effects and consequences, and in attempting to define it, as is occasionally done, the courts ordinarily assume that the idea is one which is so thoroughly understood that a formal definition is unnecessary. The idea involved in the term is the idea of breaking; and as applied to a contract, it is of course used in a figurative sense. It implies a violation of a valid and subsisting obligation. While occasionally emphasis is given to failure to perform as the essential idea of breach, it is not every failure to perform the covenants of a contract which amounts to a breach, since the contract, although valid at the outset, may have been discharged, as by a new contract,1 or by merger in some obligation of a higher character,2 or by breach of an express condition,3 or by impossibility,4 or by war,5 or by alteration.8 In all of these cases non-performance may exist without breach.
On the other hand, breach may exist without non-performance, as in jurisdictions in which the repudiation of the obligation of a contract by one of the parties before the time for performance may give to the other party the right to treat such repudiation as a breach without waiting for the time fixed by the terms of the original contract for performance.7 In the cases in which a contract has been discharged there is, however, no obligation remaining to be violated; and in jurisdictions in which renunciation in advance may be treated as breach, the party who renounces the contract is regarded as violating his duty to treat such contract as a valid and subsisting obligation until the time fixed by the terms of such contract for the performance thereof.8 The violation of a valid and subsisting obligation is, therefore, the essential idea of breach.
1 See ch. LXXV. 2 See ch. LXXVI. 3 See ch. LXXVIl.
4 See ch. LXXVIII.
5 See ch. LXX1X.
6 See ch. LXXXV.