Combining Texts

All the ideas for 'On Second-Order Logic', 'Commentary on 'Posterior Analytics' and 'works'

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18 ideas

4. Formal Logic / G. Formal Mereology / 1. Mereology
Abelard's mereology involves privileged and natural divisions, and principal parts [Abelard, by King,P]
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]
8. Modes of Existence / E. Nominalism / 1. Nominalism / b. Nominalism about universals
If 'animal' is wholly present in Socrates and an ass, then 'animal' is rational and irrational [Abelard, by King,P]
Abelard was an irrealist about virtually everything apart from concrete individuals [Abelard, by King,P]
8. Modes of Existence / E. Nominalism / 3. Predicate Nominalism
Only words can be 'predicated of many'; the universality is just in its mode of signifying [Abelard, by Panaccio]
10. Modality / A. Necessity / 4. De re / De dicto modality
The de dicto-de re modality distinction dates back to Abelard [Abelard, by Orenstein]
18. Thought / E. Abstraction / 8. Abstractionism Critique
Abelard's problem is the purely singular aspects of things won't account for abstraction [Panaccio on Abelard]
Abstraction from an ambiguous concept like 'mole' will define them as the same [Barnes,J]
Abstraction cannot produce the concept of a 'game', as there is no one common feature [Barnes,J]
Defining concepts by abstractions will collect together far too many attributes from entities [Barnes,J]
19. Language / C. Assigning Meanings / 3. Predicates
Nothing external can truly be predicated of an object [Abelard, by Panaccio]
26. Natural Theory / B. Natural Kinds / 7. Critique of Kinds
Natural kinds are not special; they are just well-defined resemblance collections [Abelard, by King,P]