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All the ideas for 'works', 'Objections to 'Meditations' (Fifth)' and 'What Required for Foundation for Maths?'

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58 ideas

2. Reason / D. Definition / 2. Aims of Definition
Definitions make our intuitions mathematically useful [Mayberry]
2. Reason / E. Argument / 6. Conclusive Proof
Proof shows that it is true, but also why it must be true [Mayberry]
3. Truth / A. Truth Problems / 6. Verisimilitude
Truth does not admit of more and less [Frege]
4. Formal Logic / F. Set Theory ST / 1. Set Theory
Frege did not think of himself as working with sets [Frege, by Hart,WD]
4. Formal Logic / F. Set Theory ST / 3. Types of Set / b. Empty (Null) Set
The null set is indefensible, because it collects nothing [Frege, by Burge]
4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / a. Axioms for sets
Set theory can't be axiomatic, because it is needed to express the very notion of axiomatisation [Mayberry]
There is a semi-categorical axiomatisation of set-theory [Mayberry]
4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / f. Axiom of Infinity V
The misnamed Axiom of Infinity says the natural numbers are finite in size [Mayberry]
4. Formal Logic / F. Set Theory ST / 5. Conceptions of Set / c. Logical sets
Frege proposed a realist concept of a set, as the extension of a predicate or concept or function [Frege, by Benardete,JA]
4. Formal Logic / F. Set Theory ST / 5. Conceptions of Set / e. Iterative sets
The set hierarchy doesn't rely on the dubious notion of 'generating' them [Mayberry]
4. Formal Logic / F. Set Theory ST / 5. Conceptions of Set / f. Limitation of Size
Limitation of size is part of the very conception of a set [Mayberry]
5. Theory of Logic / A. Overview of Logic / 2. History of Logic
The mainstream of modern logic sees it as a branch of mathematics [Mayberry]
5. Theory of Logic / A. Overview of Logic / 3. Value of Logic
Frege frequently expressed a contempt for language [Frege, by Dummett]
5. Theory of Logic / A. Overview of Logic / 5. First-Order Logic
First-order logic only has its main theorems because it is so weak [Mayberry]
5. Theory of Logic / A. Overview of Logic / 7. Second-Order Logic
Only second-order logic can capture mathematical structure up to isomorphism [Mayberry]
5. Theory of Logic / C. Ontology of Logic / 2. Platonism in Logic
Frege thinks there is an independent logical order of the truths, which we must try to discover [Frege, by Hart,WD]
5. Theory of Logic / E. Structures of Logic / 7. Predicates in Logic
For Frege, predicates are names of functions that map objects onto the True and False [Frege, by McGinn]
Frege gives a functional account of predication so that we can dispense with predicates [Frege, by Benardete,JA]
5. Theory of Logic / G. Quantification / 2. Domain of Quantification
Frege always, and fatally, neglected the domain of quantification [Dummett on Frege]
Big logic has one fixed domain, but standard logic has a domain for each interpretation [Mayberry]
5. Theory of Logic / I. Semantics of Logic / 3. Logical Truth
Basic truths of logic are not proved, but seen as true when they are understood [Frege, by Burge]
5. Theory of Logic / J. Model Theory in Logic / 3. Löwenheim-Skolem Theorems
No Löwenheim-Skolem logic can axiomatise real analysis [Mayberry]
5. Theory of Logic / K. Features of Logics / 1. Axiomatisation
'Classificatory' axioms aim at revealing similarity in morphology of structures [Mayberry]
Axiomatiation relies on isomorphic structures being essentially the same [Mayberry]
'Eliminatory' axioms get rid of traditional ideal and abstract objects [Mayberry]
5. Theory of Logic / K. Features of Logics / 6. Compactness
No logic which can axiomatise arithmetic can be compact or complete [Mayberry]
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / g. Real numbers
Real numbers can be eliminated, by axiom systems for complete ordered fields [Mayberry]
6. Mathematics / A. Nature of Mathematics / 4. Using Numbers / b. Quantity
Greek quantities were concrete, and ratio and proportion were their science [Mayberry]
Real numbers were invented, as objects, to simplify and generalise 'quantity' [Mayberry]
6. Mathematics / A. Nature of Mathematics / 5. The Infinite / a. The Infinite
Cantor's infinite is an absolute, of all the sets or all the ordinal numbers [Mayberry]
Cantor extended the finite (rather than 'taming the infinite') [Mayberry]
6. Mathematics / B. Foundations for Mathematics / 1. Foundations for Mathematics
If proof and definition are central, then mathematics needs and possesses foundations [Mayberry]
The ultimate principles and concepts of mathematics are presumed, or grasped directly [Mayberry]
Foundations need concepts, definition rules, premises, and proof rules [Mayberry]
Axiom theories can't give foundations for mathematics - that's using axioms to explain axioms [Mayberry]
6. Mathematics / B. Foundations for Mathematics / 4. Axioms for Number / d. Peano arithmetic
1st-order PA is only interesting because of results which use 2nd-order PA [Mayberry]
6. Mathematics / B. Foundations for Mathematics / 4. Axioms for Number / g. Incompleteness of Arithmetic
It is only 2nd-order isomorphism which suggested first-order PA completeness [Mayberry]
6. Mathematics / B. Foundations for Mathematics / 5. Definitions of Number / c. Fregean numbers
If '5' is the set of all sets with five members, that may be circular, and you can know a priori if the set has content [Benardete,JA on Frege]
6. Mathematics / B. Foundations for Mathematics / 6. Mathematics as Set Theory / a. Mathematics is set theory
Set theory is not just first-order ZF, because that is inadequate for mathematics [Mayberry]
We don't translate mathematics into set theory, because it comes embodied in that way [Mayberry]
Set theory is not just another axiomatised part of mathematics [Mayberry]
6. Mathematics / C. Sources of Mathematics / 6. Logicism / a. Early logicism
Frege aimed to discover the logical foundations which justify arithmetical judgements [Frege, by Burge]
Eventually Frege tried to found arithmetic in geometry instead of in logic [Frege, by Friend]
7. Existence / A. Nature of Existence / 3. Being / i. Deflating being
Frege's logic showed that there is no concept of being [Frege, by Scruton]
9. Objects / A. Existence of Objects / 2. Abstract Objects / a. Nature of abstracta
Real numbers as abstracted objects are now treated as complete ordered fields [Mayberry]
9. Objects / F. Identity among Objects / 5. Self-Identity
Frege made identity a logical notion, enshrined above all in the formula 'for all x, x=x' [Frege, by Benardete,JA]
11. Knowledge Aims / A. Knowledge / 2. Understanding
To understand a thought, understand its inferential connections to other thoughts [Frege, by Burge]
12. Knowledge Sources / A. A Priori Knowledge / 2. Self-Evidence
Frege's concept of 'self-evident' makes no reference to minds [Frege, by Burge]
12. Knowledge Sources / A. A Priori Knowledge / 4. A Priori as Necessities
An apriori truth is grounded in generality, which is universal quantification [Frege, by Burge]
14. Science / B. Scientific Theories / 1. Scientific Theory
The building blocks contain the whole contents of a discipline [Frege]
17. Mind and Body / A. Mind-Body Dualism / 2. Interactionism
Things must have parts to intermingle [Gassendi]
18. Thought / E. Abstraction / 8. Abstractionism Critique
Frege said concepts were abstract entities, not mental entities [Frege, by Putnam]
19. Language / A. Nature of Meaning / 4. Meaning as Truth-Conditions
A thought is not psychological, but a condition of the world that makes a sentence true [Frege, by Miller,A]
19. Language / C. Assigning Meanings / 5. Fregean Semantics
Frege's 'sense' is the strict and literal meaning, stripped of tone [Frege, by Miller,A]
'Sense' solves the problems of bearerless names, substitution in beliefs, and informativeness [Frege, by Miller,A]
19. Language / E. Analyticity / 1. Analytic Propositions
'P or not-p' seems to be analytic, but does not fit Kant's account, lacking clear subject or predicate [Frege, by Weiner]
19. Language / E. Analyticity / 2. Analytic Truths
Analytic truths are those that can be demonstrated using only logic and definitions [Frege, by Miller,A]
28. God / B. Proving God / 2. Proofs of Reason / a. Ontological Proof
Frege put forward an ontological argument for the existence of numbers [Frege, by Benardete,JA]