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All the ideas for 'fragments/reports', 'fragments/reports' and 'Philosophy of Mathematics'

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104 ideas

2. Reason / B. Laws of Thought / 2. Sufficient Reason
Everything happens necessarily, and for a reason [Democritus]
2. Reason / D. Definition / 8. Impredicative Definition
Impredicative definitions are wrong, because they change the set that is being defined? [Bostock]
4. Formal Logic / E. Nonclassical Logics / 2. Intuitionist Logic
Classical interdefinitions of logical constants and quantifiers is impossible in intuitionism [Bostock]
4. Formal Logic / F. Set Theory ST / 1. Set Theory
There is no single agreed structure for set theory [Bostock]
4. Formal Logic / F. Set Theory ST / 3. Types of Set / a. Types of set
A 'proper class' cannot be a member of anything [Bostock]
4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / a. Axioms for sets
We could add axioms to make sets either as small or as large as possible [Bostock]
4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / j. Axiom of Choice IX
The Axiom of Choice relies on reference to sets that we are unable to describe [Bostock]
4. Formal Logic / F. Set Theory ST / 5. Conceptions of Set / f. Limitation of Size
Replacement enforces a 'limitation of size' test for the existence of sets [Bostock]
5. Theory of Logic / A. Overview of Logic / 5. First-Order Logic
The completeness of first-order logic implies its compactness [Bostock]
First-order logic is not decidable: there is no test of whether any formula is valid [Bostock]
5. Theory of Logic / G. Quantification / 4. Substitutional Quantification
Substitutional quantification is just standard if all objects in the domain have a name [Bostock]
5. Theory of Logic / H. Proof Systems / 4. Natural Deduction
The Deduction Theorem is what licenses a system of natural deduction [Bostock]
5. Theory of Logic / L. Paradox / 4. Paradoxes in Logic / c. Berry's paradox
Berry's Paradox considers the meaning of 'The least number not named by this name' [Bostock]
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / b. Types of number
ω + 1 is a new ordinal, but its cardinality is unchanged [Bostock]
Each addition changes the ordinality but not the cardinality, prior to aleph-1 [Bostock]
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / c. Priority of numbers
A cardinal is the earliest ordinal that has that number of predecessors [Bostock]
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / f. Cardinal numbers
Aleph-1 is the first ordinal that exceeds aleph-0 [Bostock]
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / g. Real numbers
Instead of by cuts or series convergence, real numbers could be defined by axioms [Bostock]
The number of reals is the number of subsets of the natural numbers [Bostock]
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / i. Reals from cuts
For Eudoxus cuts in rationals are unique, but not every cut makes a real number [Bostock]
6. Mathematics / A. Nature of Mathematics / 4. Using Numbers / a. Units
Two can't be a self-contained unit, because it would need to be one to do that [Democritus, by Aristotle]
6. Mathematics / A. Nature of Mathematics / 5. The Infinite / k. Infinitesimals
Infinitesimals are not actually contradictory, because they can be non-standard real numbers [Bostock]
6. Mathematics / B. Foundations for Mathematics / 3. Axioms for Geometry
Modern axioms of geometry do not need the real numbers [Bostock]
6. Mathematics / B. Foundations for Mathematics / 4. Axioms for Number / d. Peano arithmetic
The Peano Axioms describe a unique structure [Bostock]
6. Mathematics / B. Foundations for Mathematics / 5. Definitions of Number / d. Hume's Principle
There are many criteria for the identity of numbers [Bostock]
Hume's Principle is a definition with existential claims, and won't explain numbers [Bostock]
Many things will satisfy Hume's Principle, so there are many interpretations of it [Bostock]
6. Mathematics / B. Foundations for Mathematics / 5. Definitions of Number / e. Caesar problem
Frege makes numbers sets to solve the Caesar problem, but maybe Caesar is a set! [Bostock]
6. Mathematics / B. Foundations for Mathematics / 7. Mathematical Structuralism / e. Structuralism critique
Numbers can't be positions, if nothing decides what position a given number has [Bostock]
Structuralism falsely assumes relations to other numbers are numbers' only properties [Bostock]
6. Mathematics / C. Sources of Mathematics / 3. Mathematical Nominalism
Nominalism about mathematics is either reductionist, or fictionalist [Bostock]
Nominalism as based on application of numbers is no good, because there are too many applications [Bostock]
6. Mathematics / C. Sources of Mathematics / 4. Mathematical Empiricism / b. Indispensability of mathematics
Actual measurement could never require the precision of the real numbers [Bostock]
6. Mathematics / C. Sources of Mathematics / 5. Numbers as Adjectival
Ordinals are mainly used adjectively, as in 'the first', 'the second'... [Bostock]
6. Mathematics / C. Sources of Mathematics / 6. Logicism / b. Type theory
Simple type theory has 'levels', but ramified type theory has 'orders' [Bostock]
6. Mathematics / C. Sources of Mathematics / 6. Logicism / c. Neo-logicism
Neo-logicists agree that HP introduces number, but also claim that it suffices for the job [Bostock]
Neo-logicists meet the Caesar problem by saying Hume's Principle is unique to number [Bostock]
6. Mathematics / C. Sources of Mathematics / 6. Logicism / d. Logicism critique
Treating numbers as objects doesn't seem like logic, since arithmetic fixes their totality [Bostock]
Many crucial logicist definitions are in fact impredicative [Bostock]
If Hume's Principle is the whole story, that implies structuralism [Bostock]
6. Mathematics / C. Sources of Mathematics / 9. Fictional Mathematics
Higher cardinalities in sets are just fairy stories [Bostock]
A fairy tale may give predictions, but only a true theory can give explanations [Bostock]
6. Mathematics / C. Sources of Mathematics / 10. Constructivism / c. Conceptualism
The best version of conceptualism is predicativism [Bostock]
Conceptualism fails to grasp mathematical properties, infinity, and objective truth values [Bostock]
6. Mathematics / C. Sources of Mathematics / 10. Constructivism / d. Predicativism
The usual definitions of identity and of natural numbers are impredicative [Bostock]
If abstracta only exist if they are expressible, there can only be denumerably many of them [Bostock]
Predicativism makes theories of huge cardinals impossible [Bostock]
If mathematics rests on science, predicativism may be the best approach [Bostock]
If we can only think of what we can describe, predicativism may be implied [Bostock]
The predicativity restriction makes a difference with the real numbers [Bostock]
7. Existence / A. Nature of Existence / 3. Being / a. Nature of Being
True Being only occurs when it is completely full, with atoms and no void [Democritus, by Aristotle]
7. Existence / A. Nature of Existence / 3. Being / d. Non-being
Being does not exist more than non-being [Democritus, by Aristotle]
The non-existent exists as much as the existent, because it has causal powers [Democritus]
7. Existence / A. Nature of Existence / 3. Being / g. Particular being
The only distinctions are Configuration (shape), Disposition (order) and Turning (position) [Democritus, by Aristotle]
7. Existence / B. Change in Existence / 1. Nature of Change
Nothing comes from non-existence, or passes into it [Democritus, by Diog. Laertius]
7. Existence / E. Categories / 5. Category Anti-Realism
It is not possible to know what sort each thing is [Democritus]
9. Objects / B. Unity of Objects / 1. Unifying an Object / b. Unifying aggregates
Democritus denies reality to large objects, because atomic entities can't combine to produce new ones [Benardete,JA on Democritus]
9. Objects / B. Unity of Objects / 2. Substance / d. Substance defined
Democritus said that substances could never be mixed, so atoms are the substances [Democritus, by Aristotle]
12. Knowledge Sources / B. Perception / 2. Qualities in Perception / a. Qualities in perception
Sensible qualities can't be real if they appear different to different creatures [Democritus, by Theophrastus]
12. Knowledge Sources / B. Perception / 3. Representation
Man is separated from reality [Democritus]
12. Knowledge Sources / C. Rationalism / 1. Rationalism
All evidence comes from senses, so they are indispensable to the mind [Democritus]
Obscure knowledge belongs to the five senses, and genuine knowledge is the other type [Democritus]
13. Knowledge Criteria / A. Justification Problems / 3. Internal or External / a. Pro-internalism
Knowledge is mind and knowing 'cohabiting' [Lycophron, by Aristotle]
13. Knowledge Criteria / D. Scepticism / 1. Scepticism
Democritus says there is either no truth, or it is concealed from us [Democritus, by Aristotle]
We actually know nothing, and opinions are mere flux [Democritus]
We in fact know nothing, but we each restructure our reality with beliefs [Democritus]
It is obviously impossible to understand the reality of each thing [Democritus]
We know nothing in reality; for truth lies in an abyss [Democritus]
14. Science / D. Explanation / 2. Types of Explanation / g. Causal explanations
Democritus was devoted to discovering causal explanations [Democritus, by Eusebius]
15. Nature of Minds / A. Nature of Mind / 2. Psuche
Democritus says soul consists of smooth round bodies brought together in accidental collision [Democritus, by Cicero]
Atomists say soul has a rational part in the chest, and a diffused non-rational part [Democritus, by Aetius]
The soul is the same as the mind [Democritus, by Aristotle]
15. Nature of Minds / A. Nature of Mind / 7. Animal Minds
Animals have a share of reason [Democritus, by Porphyry]
15. Nature of Minds / A. Nature of Mind / 8. Brain
The directive centre is located in the whole head [Democritus, by Ps-Plutarch]
16. Persons / F. Free Will / 6. Determinism / a. Determinism
Democritus said everything happens of necessity, by natural motion of atoms [Democritus, by Cicero]
Some say there is a determinate cause for every apparently spontaneous event [Democritus, by Aristotle]
Democritus said atoms only move by their natural motions, which are therefore necessary [Democritus, by Cicero]
17. Mind and Body / E. Mind as Physical / 1. Physical Mind
Democritus says spherical atoms are fire, and constitute the soul [psuche] [Democritus, by Aristotle]
Democritus says the soul is the body, and thinking is thus the mixture of the body [Democritus, by Theophrastus]
19. Language / F. Communication / 2. Assertion
In logic a proposition means the same when it is and when it is not asserted [Bostock]
20. Action / C. Motives for Action / 1. Acting on Desires
Pleasure and pain guide our choices of good and bad [Democritus]
22. Metaethics / B. Value / 2. Values / d. Health
Wisdom creates a healthy passion-free soul [Democritus]
22. Metaethics / C. The Good / 1. Goodness / f. Good as pleasure
Happiness is identifying and separating the pleasures [Democritus, by Stobaeus]
23. Ethics / C. Virtue Theory / 2. Elements of Virtue Theory / f. The Mean
Contentment comes from moderation and proportion in life [Democritus, by Stobaeus]
23. Ethics / C. Virtue Theory / 4. External Goods / c. Wealth
Democritus says wealth is a burden to the virtuous mind [Democritus, by Seneca]
26. Natural Theory / A. Speculations on Nature / 6. Early Matter Theories / g. Atomism
Atoms cling together, until a stronger necessity disperses them [Democritus, by Aristotle]
Atoms are irregular, hooked, concave, convex, and many other shapes [Democritus, by Aristotle]
'Full' and 'Void' secularised Parmenides's Being and Not-being [Democritus, by Heisenberg]
Atomists say there are only three differences - in shape, arrangement and position [Democritus, by Aristotle]
Experiences are merely convention; only atoms and the void are real [Democritus]
If only atoms are real and the rest is convention, we wouldn't bother to avoid pain [Democritus, by Diogenes of Oen.]
When atoms touch, why don't they coalesce, like water drops? [Aristotle on Democritus]
Because appearance is infinitely varied, atomists assume infinitely many shapes of atom [Democritus, by Aristotle]
There could be an atom the size of the world [Democritus, by Ps-Plutarch]
There must be atoms, to avoid the absurdity of infinite division down to nothing [Democritus, by Aristotle]
The basic atoms are without qualities - which only arise from encounters between atoms [Democritus, by Galen]
If a cone is horizontally sliced the surfaces can't be equal, so it goes up in steps [Democritus]
26. Natural Theory / D. Laws of Nature / 1. Laws of Nature
Greeks explained regularity by intellectual design, not by laws [Democritus, by Frede,M]
27. Natural Reality / C. Space / 1. Void
Growth and movement would not exist if there were no void to receive them [Democritus]
Democritus is wrong: in a void we wouldn't see a distant ant in exact detail [Aristotle on Democritus]
Movement is impossible in a void, because nothing can decide the direction of movement [Aristotle on Democritus]
27. Natural Reality / E. Cosmology / 1. Cosmology
There are unlimited worlds of varying sizes, some without life or water [Democritus, by Hippolytus]
28. God / B. Proving God / 3. Proofs of Evidence / c. Teleological Proof critique
Democritus said people imagined gods as the source of what awed or frightened them [Democritus, by Sext.Empiricus]
29. Religion / D. Religious Issues / 2. Immortality / a. Immortality
The soul is destroyed with the body [Democritus, by Ps-Plutarch]