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All the ideas for 'Posthumous notes', 'fragments/reports' and 'Nature and Meaning of Numbers'

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51 ideas

2. Reason / A. Nature of Reason / 1. On Reason
Parmenides was much more cautious about accepting ideas than his predecessors [Simplicius on Parmenides]
2. Reason / D. Definition / 9. Recursive Definition
Dedekind proved definition by recursion, and thus proved the basic laws of arithmetic [Dedekind, by Potter]
4. Formal Logic / F. Set Theory ST / 3. Types of Set / d. Infinite Sets
An infinite set maps into its own proper subset [Dedekind, by Reck/Price]
4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / f. Axiom of Infinity V
We have the idea of self, and an idea of that idea, and so on, so infinite ideas are available [Dedekind, by Potter]
4. Formal Logic / G. Formal Mereology / 1. Mereology
Dedekind originally thought more in terms of mereology than of sets [Dedekind, by Potter]
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / a. Numbers
Numbers are free creations of the human mind, to understand differences [Dedekind]
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / c. Priority of numbers
Dedekind defined the integers, rationals and reals in terms of just the natural numbers [Dedekind, by George/Velleman]
Order, not quantity, is central to defining numbers [Dedekind, by Monk]
Ordinals can define cardinals, as the smallest ordinal that maps the set [Dedekind, by Heck]
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / e. Ordinal numbers
Dedekind's ordinals are just members of any progression whatever [Dedekind, by Russell]
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / i. Reals from cuts
Dedekind's axiom that his Cut must be filled has the advantages of theft over honest toil [Dedekind, by Russell]
Dedekind says each cut matches a real; logicists say the cuts are the reals [Dedekind, by Bostock]
6. Mathematics / A. Nature of Mathematics / 4. Using Numbers / c. Counting procedure
In counting we see the human ability to relate, correspond and represent [Dedekind]
6. Mathematics / A. Nature of Mathematics / 5. The Infinite / b. Mark of the infinite
A system S is said to be infinite when it is similar to a proper part of itself [Dedekind]
6. Mathematics / B. Foundations for Mathematics / 4. Axioms for Number / a. Axioms for numbers
Dedekind gives a base number which isn't a successor, then adds successors and induction [Dedekind, by Hart,WD]
6. Mathematics / B. Foundations for Mathematics / 4. Axioms for Number / d. Peano arithmetic
Zero is a member, and all successors; numbers are the intersection of sets satisfying this [Dedekind, by Bostock]
6. Mathematics / B. Foundations for Mathematics / 4. Axioms for Number / e. Peano arithmetic 2nd-order
Categoricity implies that Dedekind has characterised the numbers, because it has one domain [Rumfitt on Dedekind]
6. Mathematics / B. Foundations for Mathematics / 4. Axioms for Number / f. Mathematical induction
Induction is proved in Dedekind, an axiom in Peano; the latter seems simpler and clearer [Dedekind, by Russell]
6. Mathematics / B. Foundations for Mathematics / 7. Mathematical Structuralism / a. Structuralism
Dedekind originated the structuralist conception of mathematics [Dedekind, by MacBride]
6. Mathematics / B. Foundations for Mathematics / 7. Mathematical Structuralism / b. Varieties of structuralism
Dedekindian abstraction talks of 'positions', where Cantorian abstraction talks of similar objects [Dedekind, by Fine,K]
7. Existence / A. Nature of Existence / 3. Being / a. Nature of Being
Being is not divisible, since it is all alike [Parmenides]
No necessity could produce Being either later or earlier, so it must exist absolutely or not at all [Parmenides]
Being must be eternal and uncreated, and hence it is timeless [Parmenides]
7. Existence / A. Nature of Existence / 3. Being / d. Non-being
The realm of necessary non-existence cannot be explored, because it is unknowable [Parmenides]
There is no such thing as nothing [Parmenides]
7. Existence / A. Nature of Existence / 3. Being / f. Primary being
Parmenides at least saw Being as the same as Nous, and separate from the sensed realm [Parmenides, by Plotinus]
7. Existence / B. Change in Existence / 1. Nature of Change
All our concepts of change and permanence are just names, not the truth [Parmenides]
9. Objects / A. Existence of Objects / 3. Objects in Thought
A thing is completely determined by all that can be thought concerning it [Dedekind]
9. Objects / E. Objects over Time / 1. Objects over Time
Something must be unchanging to make recognition and knowledge possible [Aristotle on Parmenides]
10. Modality / A. Necessity / 5. Metaphysical Necessity
The first way of enquiry involves necessary existence [Parmenides]
10. Modality / A. Necessity / 8. Transcendental Necessity
Necessity sets limits on being, in order to give it identity [Parmenides]
11. Knowledge Aims / B. Certain Knowledge / 4. The Cogito
Thinking implies existence, because thinking depends on it [Parmenides]
11. Knowledge Aims / C. Knowing Reality / 3. Idealism / d. Absolute idealism
Transcendental philosophy is the subject becoming the originator of unified reality [Kant]
12. Knowledge Sources / B. Perception / 1. Perception
Parmenides treats perception and intellectual activity as the same [Theophrastus on Parmenides]
12. Knowledge Sources / C. Rationalism / 1. Rationalism
Only reason can prove the truth of facts [Parmenides]
18. Thought / E. Abstraction / 3. Abstracta by Ignoring
Dedekind said numbers were abstracted from systems of objects, leaving only their position [Dedekind, by Dummett]
We derive the natural numbers, by neglecting everything of a system except distinctness and order [Dedekind]
18. Thought / E. Abstraction / 8. Abstractionism Critique
Dedekind has a conception of abstraction which is not psychologistic [Dedekind, by Tait]
26. Natural Theory / A. Speculations on Nature / 6. Early Matter Theories / e. The One
People who say that the cosmos is one forget that they must explain movement [Aristotle on Parmenides]
The one is without any kind of motion [Parmenides]
There could be movement within one thing, as there is within water [Aristotle on Parmenides]
The one can't be divisible, because if it was it could be infinitely divided down to nothing [Parmenides, by Simplicius]
Defenders of the One say motion needs the void - but that is not part of Being [Parmenides, by Aristotle]
Reason sees reality as one, the senses see it as many [Aristotle on Parmenides]
Reality is symmetrical and balanced, like a sphere, with no reason to be greater one way rather than another [Parmenides]
26. Natural Theory / A. Speculations on Nature / 6. Early Matter Theories / f. Ancient elements
He taught that there are two elements, fire the maker, and earth the matter [Parmenides, by Diog. Laertius]
27. Natural Reality / A. Classical Physics / 1. Mechanics / a. Explaining movement
It is feeble-minded to look for explanations of everything being at rest [Aristotle on Parmenides]
27. Natural Reality / C. Space / 1. Void
The void can't exist, and without the void there can't be movement or separation [Parmenides, by Aristotle]
27. Natural Reality / D. Time / 3. Parts of Time / a. Beginning of time
What could have triggered the beginning [of time and being]? [Parmenides]
27. Natural Reality / E. Cosmology / 1. Cosmology
He was the first to discover the identity of the Morning and Evening Stars [Parmenides, by Diog. Laertius]
He was the first person to say the earth is spherical [Parmenides, by Diog. Laertius]