The quality of a statement, remember, refers to its being either affirmative or negative. If the statement that serves as the conclusion of an argument is negative, at least one of the premises in the argument must be negative. Let us see what happens if both of the premises of an argument are negative. No men are daughters. No waitresses are men. Therefore, no waitresses are daughters. The conclusion is manifestly false. The effect of two negative premises is comparable to that of an undistributed middle term. With an undistributed middle term, no necessary connection is made between
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