Combining Texts

All the ideas for 'works', 'On the Syllogism IV' and 'works'

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5 ideas

5. Theory of Logic / E. Structures of Logic / 6. Relations in Logic
De Morgan started the study of relations and their properties [De Morgan, by Walicki]
De Morgan found inferences involving relations, which eluded Aristotle's syllogistic [De Morgan, by Hart,WD]
5. Theory of Logic / G. Quantification / 4. Substitutional Quantification
The values of variables can't determine existence, because they are just expressions [Ryle, by Quine]
6. Mathematics / B. Foundations for Mathematics / 4. Axioms for Number / a. Axioms for numbers
Numbers have been defined in terms of 'successors' to the concept of 'zero' [Peano, by Blackburn]
6. Mathematics / B. Foundations for Mathematics / 4. Axioms for Number / d. Peano arithmetic
0 is a non-successor number, all successors are numbers, successors can't duplicate, if P(n) and P(n+1) then P(all-n) [Peano, by Flew]