Explain what is meant by 'Supervening Impossibility' as per the Indian Contract Act, 1872 with the help of an example. What is the effect of such impossibility?

According to Section 56 of the Indian Contract Act, 1872, the impossibility of performance may be of the two types, namely (a) initial impossibility, and (b) subsequent impossibility. Subsequent impossibility is also known as Supervening impossibility i.e. becomes impossible after entering into contract. When performance of promise becomes impossible or illegal by occurrence of an unexpected event or a change of circumstances beyond the contemplation of parties, the contract becomes void e.g. change in law etc. In other words, sometimes, the performance of a contract is quite possible when it is made. But subsequently, some event happens which renders the performance impossible or unlawful. Such impossibility is called the subsequent or supervening. It is also called the post-contractual impossibility. Example: ‘A’ and ‘B’ contracted to marry each other. Before the time fixed for the marriage, ‘A’ became mad. In this case, the contract becomes void due to subsequent impossibility, and thus discharged. Effect of impossibility: The effect of such impossibility is that it makes the contract void, and the parties are discharged from further performance of the contract.