52. Promisor not bound to perform unless reciprocal promisee ready and willing to perform

When a contract consists of reciprocal promises to be simultaneously performed, no promisor need perform his promise unless the promisee is ready and willing to perform his reciprocal promise.

Illustrations

A and B contract that A shall deliver goods to B to be paid for by B on delivery.

A and B contract that A shall deliver goods to B at a price to be paid by instalments, the first instalment to be paid on delivery.