But all conditions are precedent, not only in this extreme sense, but also to the existence of the plaintiff’s cause of action.  As strong a case as can be put is that of a policy of insurance conditioned to be void if not sued upon within one year from a failure to pay as agreed.  The condition does not come into play until a loss has occurred, the duty to pay has been neglected, and a cause of action has arisen.  Nevertheless, it is precedent to the plaintiff’s cause of action.  When a man sues, the question is not whether he has had a cause of action in the past, but whether he has one then.  He has not one then, unless the year is still running.  If it were left for the defendant to set up the lapse of the year, that would be due to the circumstance that the order of pleading does not require a plaintiff to meet all possible defences, and to set out a case unanswerable except by denial.  The point at which the law calls on the defendant for an answer varies [318] in different cases.  Sometimes it would seem to be governed simply by convenience of proof, requiring the party who has the affirmative to plead and prove it.  Sometimes there seems to be a reference to the usual course of events, and matters belong to the defence because they are only exceptionally true.

The most logical distinction would be between conditions which must be satisfied before a promise can be broken, and those which, like the last, discharge the liability after a breach has occurred. 1 But this is of the slightest possible importance, and it may be doubted whether another case like the last could be found.

It is much more important to mark the distinction between a stipulation which only has the effect of confining a promise to certain cases, and a condition properly so called.  Every condition, it is true, has this effect upon the promise to which it is attached, so that, whatever the rule of pleading may be, 2 a promise is as truly kept and performed by doing nothing where the condition of the stipulated act has been broken, as it would have been by doing the act if the condition had been fulfilled.  But if this were all, every clause in a contract which showed what the promisor did not promise would be a condition, and the word would be worse than useless.  The characteristic feature is quite different.

A condition properly so called is an event, the happening of which authorizes the person in whose favor the condition is reserved to treat the contract as if it had not been made,—­to avoid it, as is commonly said,—­that is, to insist on both parties being restored to the position in [319] which they stood before the contract was made.  When a condition operates as such, it lets in an outside force to destroy the existing state of things.  For although its existence is due to consent of parties, its operation depends on the choice of one of them.  When a condition is broken, the person entitled to insist on it may do so if he chooses; but he may, if he prefers, elect to keep the contract on foot.  He gets his right to avoid it from the agreement, but the avoidance comes from him.