Combining Texts

All the ideas for 'Matter and Memory', 'Intro to 2nd ed of Principia Mathematica' and 'On Second-Order Logic'

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10 ideas

5. Theory of Logic / A. Overview of Logic / 7. Second-Order Logic
Boolos reinterprets second-order logic as plural logic [Boolos, by Oliver/Smiley]
Second-order logic metatheory is set-theoretic, and second-order validity has set-theoretic problems [Boolos]
5. Theory of Logic / C. Ontology of Logic / 1. Ontology of Logic
A sentence can't be a truth of logic if it asserts the existence of certain sets [Boolos]
5. Theory of Logic / G. Quantification / 2. Domain of Quantification
'∀x x=x' only means 'everything is identical to itself' if the range of 'everything' is fixed [Boolos]
5. Theory of Logic / K. Features of Logics / 4. Completeness
Weak completeness: if it is valid, it is provable. Strong: it is provable from a set of sentences [Boolos]
5. Theory of Logic / K. Features of Logics / 6. Compactness
Why should compactness be definitive of logic? [Boolos, by Hacking]
6. Mathematics / B. Foundations for Mathematics / 4. Axioms for Number / e. Peano arithmetic 2nd-order
Many concepts can only be expressed by second-order logic [Boolos]
7. Existence / A. Nature of Existence / 3. Being / c. Becoming
Bergson was a rallying point, because he emphasised becomings and multiplicities [Bergson, by Deleuze]
7. Existence / C. Structure of Existence / 6. Fundamentals / d. Logical atoms
Given all true atomic propositions, in theory every other truth can thereby be deduced [Russell]
12. Knowledge Sources / E. Direct Knowledge / 4. Memory
Bergson showed that memory is not after the event, but coexists with it [Bergson, by Deleuze]