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All the ideas for 'Analyzing Modality', 'A Subject with No Object' and 'Logic in Mathematics'

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49 ideas

2. Reason / D. Definition / 3. Types of Definition
A 'constructive' (as opposed to 'analytic') definition creates a new sign [Frege]
2. Reason / D. Definition / 10. Stipulative Definition
Frege suggested that mathematics should only accept stipulative definitions [Frege, by Gupta]
2. Reason / E. Argument / 6. Conclusive Proof
We must be clear about every premise and every law used in a proof [Frege]
3. Truth / H. Deflationary Truth / 2. Deflationary Truth
'True' is only occasionally useful, as in 'everything Fermat believed was true' [Burgess/Rosen]
4. Formal Logic / D. Modal Logic ML / 1. Modal Logic
Modal logic gives an account of metalogical possibility, not metaphysical possibility [Burgess/Rosen]
4. Formal Logic / F. Set Theory ST / 5. Conceptions of Set / d. Naïve logical sets
The paradoxes are only a problem for Frege; Cantor didn't assume every condition determines a set [Burgess/Rosen]
4. Formal Logic / G. Formal Mereology / 1. Mereology
Mereology implies that acceptance of entities entails acceptance of conglomerates [Burgess/Rosen]
5. Theory of Logic / A. Overview of Logic / 3. Value of Logic
Logic not only proves things, but also reveals logical relations between them [Frege]
5. Theory of Logic / A. Overview of Logic / 8. Logic of Mathematics
Does some mathematical reasoning (such as mathematical induction) not belong to logic? [Frege]
The closest subject to logic is mathematics, which does little apart from drawing inferences [Frege]
5. Theory of Logic / E. Structures of Logic / 6. Relations in Logic
A relation is either a set of sets of sets, or a set of sets [Burgess/Rosen]
5. Theory of Logic / E. Structures of Logic / 8. Theories in Logic
'Theorems' are both proved, and used in proofs [Frege]
5. Theory of Logic / G. Quantification / 3. Objectual Quantification
'All horses' either picks out the horses, or the things which are horses [Jubien]
5. Theory of Logic / K. Features of Logics / 1. Axiomatisation
Tracing inference backwards closes in on a small set of axioms and postulates [Frege]
The essence of mathematics is the kernel of primitive truths on which it rests [Frege]
A truth can be an axiom in one system and not in another [Frege]
Axioms are truths which cannot be doubted, and for which no proof is needed [Frege]
5. Theory of Logic / L. Paradox / 5. Paradoxes in Set Theory / a. Set theory paradoxes
The paradoxes no longer seem crucial in critiques of set theory [Burgess/Rosen]
6. Mathematics / A. Nature of Mathematics / 1. Mathematics
To create order in mathematics we need a full system, guided by patterns of inference [Frege]
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / a. Numbers
We should talk about possible existence, rather than actual existence, of numbers [Burgess/Rosen]
6. Mathematics / B. Foundations for Mathematics / 4. Axioms for Number / a. Axioms for numbers
If principles are provable, they are theorems; if not, they are axioms [Frege]
6. Mathematics / B. Foundations for Mathematics / 7. Mathematical Structuralism / c. Nominalist structuralism
Structuralism and nominalism are normally rivals, but might work together [Burgess/Rosen]
6. Mathematics / C. Sources of Mathematics / 1. Mathematical Platonism / b. Against mathematical platonism
Number words became nouns around the time of Plato [Burgess/Rosen]
7. Existence / C. Structure of Existence / 7. Abstract/Concrete / a. Abstract/concrete
Abstract/concrete is a distinction of kind, not degree [Burgess/Rosen]
Much of what science says about concrete entities is 'abstraction-laden' [Burgess/Rosen]
7. Existence / C. Structure of Existence / 7. Abstract/Concrete / b. Levels of abstraction
Mathematics has ascended to higher and higher levels of abstraction [Burgess/Rosen]
Abstraction is on a scale, of sets, to attributes, to type-formulas, to token-formulas [Burgess/Rosen]
9. Objects / A. Existence of Objects / 1. Physical Objects
Being a physical object is our most fundamental category [Jubien]
9. Objects / A. Existence of Objects / 5. Individuation / d. Individuation by haecceity
Haecceities implausibly have no qualities [Jubien]
9. Objects / B. Unity of Objects / 3. Unity Problems / e. Vague objects
Every concept must have a sharp boundary; we cannot allow an indeterminate third case [Frege]
10. Modality / A. Necessity / 11. Denial of Necessity
De re necessity is just de dicto necessity about object-essences [Jubien]
10. Modality / C. Sources of Modality / 5. Modality from Actuality
Modal propositions transcend the concrete, but not the actual [Jubien]
Your properties, not some other world, decide your possibilities [Jubien]
Modal truths are facts about parts of this world, not about remote maximal entities [Jubien]
10. Modality / E. Possible worlds / 1. Possible Worlds / e. Against possible worlds
We have no idea how many 'possible worlds' there might be [Jubien]
If there are no other possible worlds, do we then exist necessarily? [Jubien]
If all possible worlds just happened to include stars, their existence would be necessary [Jubien]
Possible worlds just give parallel contingencies, with no explanation at all of necessity [Jubien]
If other worlds exist, then they are scattered parts of the actual world [Jubien]
Worlds don't explain necessity; we use necessity to decide on possible worlds [Jubien]
10. Modality / E. Possible worlds / 3. Transworld Objects / c. Counterparts
We mustn't confuse a similar person with the same person [Jubien]
18. Thought / B. Mechanics of Thought / 5. Mental Files
We need definitions to cram retrievable sense into a signed receptacle [Frege]
We use signs to mark receptacles for complex senses [Frege]
18. Thought / E. Abstraction / 2. Abstracta by Selection
The old debate classified representations as abstract, not entities [Burgess/Rosen]
19. Language / A. Nature of Meaning / 6. Meaning as Use
A sign won't gain sense just from being used in sentences with familiar components [Frege]
19. Language / D. Propositions / 2. Abstract Propositions / a. Propositions as sense
Thoughts are not subjective or psychological, because some thoughts are the same for us all [Frege]
A thought is the sense expressed by a sentence, and is what we prove [Frege]
19. Language / D. Propositions / 5. Unity of Propositions
The parts of a thought map onto the parts of a sentence [Frege]
27. Natural Reality / C. Space / 2. Space
If space is really just a force-field, then it is a physical entity [Burgess/Rosen]