To refer a subject to a negative class is unmeaning, unless the ‘not’ is a mere modification of the positive, as in the example of ‘not honourable’ and ‘dishonourable’; or unless the class is characterized by the absence rather than the presence of a particular quality.
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That becomes clear if you try to define the objects and things which supervene in each class. Odd and even, straight and curved, number, line, and shape can be defined without change but flesh, bone, and man cannot. They are like snub nose, not like curved.