Where a transaction concerns the transfer of title or possession from one party to another, the distinction between a void and a voidable transaction is readily brought to the notice of any one dealing with the subject. Where a horse is sold, or a negotiable note transferred, a subsequent purchaser for value in good faith will acquire indefeasible ownership if the original transaction was merely voidable. If, however, the transaction in question is a non-negotiable agreement, in an action thereon, it will be generally practically unimportant for the defendant whether the transaction was void or was voidable by him. In either case he has an absolute defence; and though the other party to the transaction should assign his supposed contractual right to an innocent purchaser, the purchaser will have no greater right than the original contractor. To be sure if the agreement was merely voidable by one party, he would be at liberty to ratify the transaction and insist upon its performance, but where either party has the option of avoiding the transaction, as is frequently the situation where there is mutual mistake of fact, ratification by one is impossible. A new mutual agreement seems essential in order to preclude either party from obtaining relief. But when it is remembered that such relief is not a matter of course, that one seeking relief must sustain a heavy burden of proof, that laches and a variety of circumstances may ultimately preclude the avoidance of the contract though it was originally voidable, it is obvious that even in the case of a non-negotiable contract a distinction must be made between a transaction voidable for mistake and one where the transaction was wholly void.