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All the ideas for 'Through the Looking Glass', 'Truth Rehabilitated' and 'Logic in Mathematics'

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30 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 / A. Truth Problems / 3. Value of Truth
Without truth, both language and thought are impossible [Davidson]
Plato's Forms confused truth with the most eminent truths, so only Truth itself is completely true [Davidson]
Truth can't be a goal, because we can neither recognise it nor confim it [Davidson]
3. Truth / C. Correspondence Truth / 1. Correspondence Truth
Correspondence can't be defined, but it shows how truth depends on the world [Davidson]
3. Truth / F. Semantic Truth / 1. Tarski's Truth / c. Meta-language for truth
When Tarski defines truth for different languages, how do we know it is a single concept? [Davidson]
3. Truth / H. Deflationary Truth / 2. Deflationary Truth
Disquotation only accounts for truth if the metalanguage contains the object language [Davidson]
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 / 8. Theories in Logic
'Theorems' are both proved, and used in proofs [Frege]
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]
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 / 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]
7. Existence / A. Nature of Existence / 3. Being / e. Being and nothing
I only wish I had such eyes as to see Nobody! It's as much as I can do to see real people. [Carroll,L]
7. Existence / D. Theories of Reality / 8. Facts / e. Facts rejected
If we try to identify facts precisely, they all melt into one (as the Slingshot Argument proves) [Davidson]
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]
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]
19. Language / A. Nature of Meaning / 4. Meaning as Truth-Conditions
Knowing the potential truth conditions of a sentence is necessary and sufficient for understanding [Davidson]
19. Language / A. Nature of Meaning / 6. Meaning as Use
It could be that the use of a sentence is explained by its truth conditions [Davidson]
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]