*22. CALCULUS OF CLASSES.
Project Gutenberg EPUB3 edition
Whitehead, Alfred North and Russell, Bertrand
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Dem.
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Dem.
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This is one form of the syllogism in Barbara. Another form is the following:
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Dem.
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Dem.
The above is the law of tautology for the logical multiplication of classes.
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Thus logical multiplication of classes obeys the commutative and associative laws. References to *22·33·34·35 and to *20·43 will in future often be omitted.
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This definition serves merely for the avoidance of brackets.
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The above is the law of tautology for the logical addition of classes.
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Dem.