alleryStart learning →If it is false that all A are B, which inference is invalid?
ANo A are B
BNot every A is B
CSome A are non-B
DSome A are not B
Answer & Solution
Correct answer: A. No A are B
Denying 'all A are B' only gives 'some A are not B'; jumping to 'no A are B' is the illicit contrary.
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