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When two parties have made a contract and have expressed it in a writing to which they have both assented as the complete and accurate integration of that contract, evidence, whether parol or otherwise, of antecedent understandings and negotiations will not be admitted for the purpose of varying or contradicting the writing. This is in substance what is called the "parol evidence rule," a rule that does not deserve to be called a rule of evidence of any kind, and a rule that is as truly applicable to written evidence as to parol evidence. The use of such a name for this rule has had unfortunate consequences, principally by distracting attention from the real issues that are involved. These issues may be any one or more of the following: (1) have the parties made a contract? (2) Is that contract void or voidable because of illegality, fraud, mistake, or any other reason? (3) Did the parties assent to a particular writing as the complete and accurate integration of that contract?
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