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All the ideas for 'Philosophy of Mathematics', 'Logic [1897]' and 'Can there be Vague Objects?'

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11 ideas

2. Reason / D. Definition / 8. Impredicative Definition
Predicative definitions only refer to entities outside the defined collection [Horsten]
5. Theory of Logic / J. Model Theory in Logic / 2. Isomorphisms
A theory is 'categorical' if it has just one model up to isomorphism [Horsten]
6. Mathematics / B. Foundations for Mathematics / 2. Proof in Mathematics
Computer proofs don't provide explanations [Horsten]
6. Mathematics / B. Foundations for Mathematics / 6. Mathematics as Set Theory / a. Mathematics is set theory
The concept of 'ordinal number' is set-theoretic, not arithmetical [Horsten]
7. Existence / D. Theories of Reality / 10. Vagueness / b. Vagueness of reality
Evans argues (falsely!) that a contradiction follows from treating objects as vague [Evans, by Lowe]
Is it coherent that reality is vague, identities can be vague, and objects can have fuzzy boundaries? [Evans]
Evans assumes there can be vague identity statements, and that his proof cannot be right [Evans, by Lewis]
There clearly are vague identity statements, and Evans's argument has a false conclusion [Evans, by Lewis]
9. Objects / B. Unity of Objects / 3. Unity Problems / e. Vague objects
If a=b is indeterminate, then a=/=b, and so there cannot be indeterminate identity [Evans, by Thomasson]
9. Objects / F. Identity among Objects / 6. Identity between Objects
There can't be vague identity; a and b must differ, since a, unlike b, is only vaguely the same as b [Evans, by PG]
13. Knowledge Criteria / C. External Justification / 2. Causal Justification
Psychological logic can't distinguish justification from causes of a belief [Frege]