What is the ruling if the master claims to have received only the final portion of the *kitabah* payment?

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If the master states, "I have received the end portion of my *kitabah* payment," and subsequently claims that he only meant the final installment and not what preceded it, while the slave asserts the master acknowledged receiving the entirety, the statement of the master prevails. This is because the master possesses superior knowledge regarding his own intent.