 The parol evidence rule is inapplicable when the question before the court is whether or not the parties actually intended to draw up an exclusive memorial in the first place, and when it is apparent that a written document was not so intended; indeed, the rule applies "only" to written contracts, and comes into play only once everyone is satisfied that a contract actually exists.Furthermore, the rule does not apply if the document in question represents only one part of the contract, or if the contract is partly written and partly oral, which is the same as saying that the document was not intended, as it must, to be the whole body of the contract.It must apply to the contract in its entirety.