The reasoning in Hochster v. De La Tour,4 already adverted to, illustrates the importance of a distinction, which should be observed - the distinction between a defence and a right of action. This seems obvious, but it is frequently lost sight of, as it was in that case. It seems to be assumed that a breach of contract by one party is the only basis for a defence on the other's part. But fraud, mistake, failure of consideration actual or prospective and all other affirmative defences to breach of contract are based simply on principles of equity and justice. Whether -a breach of contract has been committed does not primarily depend on such principles, but on whether a binding promise has been broken. Every consideration of justice requires that repudiation or inability to perform should immediately excuse the innocent party from, performing, or preparing to perform, nor is any technical rule violated if the excuse is allowed. But it does not follow from this that he has an immediate right of action. Indeed even if it be assumed that repudiation before the time for performance should give rise to an immediate right of action, it is impossible to make identical requirements concerning the repudiation which will furnish a defence and that which will afford ground for an action.5 It is a consequence of allowing such a defence that the injured party not only is free from liability if he fails to perform, but that if he brings an action he shall not be defeated by reason of his own non-performance, since that failure to perform was caused by the defendant's fault.6 But though the defendant cannot defeat the action on this ground, any other defence is effectual, and there is no reason precluding him from asserting that the action is prematurely brought.