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All the ideas for 'fragments/reports', 'What Required for Foundation for Maths?' and 'Truth and Ontology'

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59 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 / B. Truthmakers / 2. Truthmaker Relation
A ground must be about its truth, and not just necessitate it [Merricks]
3. Truth / B. Truthmakers / 5. What Makes Truths / a. What makes truths
Truthmaker needs truths to be 'about' something, and that is often unclear [Merricks]
3. Truth / B. Truthmakers / 5. What Makes Truths / b. Objects make truths
If a ball changes from red to white, Truthmaker says some thing must make the change true [Merricks]
Truthmaker says if an entity is removed, some nonexistence truthmaker must replace it [Merricks]
If Truthmaker says each truth is made by the existence of something, the theory had de re modality at is core [Merricks]
3. Truth / B. Truthmakers / 5. What Makes Truths / c. States of affairs make truths
Truthmaker demands not just a predication, but an existing state of affairs with essential ingredients [Merricks]
3. Truth / B. Truthmakers / 5. What Makes Truths / d. Being makes truths
If 'truth supervenes on being', worlds with the same entities, properties and relations have the same truths [Merricks]
If truth supervenes on being, that won't explain why truth depends on being [Merricks]
3. Truth / B. Truthmakers / 6. Making Negative Truths
It is implausible that claims about non-existence are about existing things [Merricks]
3. Truth / B. Truthmakers / 11. Truthmaking and Correspondence
Truthmaker isn't the correspondence theory, because it offers no analysis of truth [Merricks]
3. Truth / B. Truthmakers / 12. Rejecting Truthmakers
Speculations about non-existent things are not about existent things, so Truthmaker is false [Merricks]
I am a truthmaker for 'that a human exists', but is it about me? [Merricks]
3. Truth / C. Correspondence Truth / 3. Correspondence Truth critique
Being true is not a relation, it is a primitive monadic property [Merricks]
If the correspondence theory is right, then necessary truths must correspond to something [Merricks]
3. Truth / H. Deflationary Truth / 2. Deflationary Truth
Deflationism just says there is no property of being truth [Merricks]
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 / 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 / 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 / G. Quantification / 2. Domain of Quantification
Big logic has one fixed domain, but standard logic has a domain for each interpretation [Mayberry]
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 / 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]
7. Existence / A. Nature of Existence / 3. Being / d. Non-being
The totality state is the most plausible truthmaker for negative existential truths [Merricks]
8. Modes of Existence / B. Properties / 3. Types of Properties
Some properties seem to be primitive, but others can be analysed [Merricks]
8. Modes of Existence / C. Powers and Dispositions / 6. Dispositions / c. Dispositions as conditional
An object can have a disposition when the revelant conditional is false [Merricks]
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 / A. Existence of Objects / 4. Impossible objects
Fregeans say 'hobbits do not exist' is just 'being a hobbit' is not exemplified [Merricks]
9. Objects / E. Objects over Time / 5. Temporal Parts
You believe you existed last year, but your segment doesn't, so they have different beliefs [Merricks]
10. Modality / B. Possibility / 9. Counterfactuals
Counterfactuals aren't about actuality, so they lack truthmakers or a supervenience base [Merricks]
10. Modality / E. Possible worlds / 3. Transworld Objects / c. Counterparts
If 'Fido is possibly black' depends on Fido's counterparts, then it has no actual truthmaker [Merricks]
26. Natural Theory / A. Speculations on Nature / 5. Infinite in Nature
Archelaus was the first person to say that the universe is boundless [Archelaus, by Diog. Laertius]
27. Natural Reality / D. Time / 1. Nature of Time / h. Presentism
Presentist should deny there is a present time, and just say that things 'exist' [Merricks]
Maybe only presentism allows change, by now having a property, and then lacking it [Merricks]
Presentists say that things have existed and will exist, not that they are instantaneous [Merricks]
27. Natural Reality / D. Time / 2. Passage of Time / k. Temporal truths
How can a presentist explain an object's having existed? [Merricks]
27. Natural Reality / G. Biology / 3. Evolution
Archelaus said life began in a primeval slime [Archelaus, by Schofield]