Combining Texts

All the ideas for 'Phaedo', 'Introduction to Zermelo's 1930 paper' and 'Nature and Meaning of Numbers'

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48 ideas

1. Philosophy / A. Wisdom / 1. Nature of Wisdom
Wisdom makes virtue and true goodness possible [Plato]
1. Philosophy / D. Nature of Philosophy / 5. Aims of Philosophy / b. Philosophy as transcendent
Philosophy is a purification of the soul ready for the afterlife [Plato]
2. Reason / A. Nature of Reason / 3. Pure Reason
In investigation the body leads us astray, but the soul gets a clear view of the facts [Plato]
2. Reason / A. Nature of Reason / 7. Status of Reason
The greatest misfortune for a person is to develop a dislike for argument [Plato]
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 / a. Axioms for sets
The first-order ZF axiomatisation is highly non-categorical [Hallett,M]
Non-categoricity reveals a sort of incompleteness, with sets existing that the axioms don't reveal [Hallett,M]
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 / F. Set Theory ST / 7. Natural Sets
Zermelo allows ur-elements, to enable the widespread application of set-theory [Hallett,M]
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]
Ordinals can define cardinals, as the smallest ordinal that maps the set [Dedekind, by Heck]
Order, not quantity, is central to defining numbers [Dedekind, by Monk]
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 / 4. Using Numbers / f. Arithmetic
If you add one to one, which one becomes two, or do they both become two? [Plato]
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 / A. Nature of Mathematics / 5. The Infinite / g. Continuum Hypothesis
The General Continuum Hypothesis and its negation are both consistent with ZF [Hallett,M]
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]
8. Modes of Existence / A. Relations / 2. Internal Relations
If Simmias is taller than Socrates, that isn't a feature that is just in Simmias [Plato]
8. Modes of Existence / D. Universals / 6. Platonic Forms / a. Platonic Forms
We must have a prior knowledge of equality, if we see 'equal' things and realise they fall short of it [Plato]
8. Modes of Existence / D. Universals / 6. Platonic Forms / b. Partaking
There is only one source for all beauty [Plato]
Other things are named after the Forms because they participate in them [Plato]
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 / 9. Ship of Theseus
The ship which Theseus took to Crete is now sent to Delos crowned with flowers [Plato]
12. Knowledge Sources / A. A Priori Knowledge / 3. Innate Knowledge / b. Recollection doctrine
People are obviously recollecting when they react to a geometrical diagram [Plato]
If we feel the inadequacy of a resemblance, we must recollect the original [Plato]
12. Knowledge Sources / A. A Priori Knowledge / 6. A Priori from Reason
To achieve pure knowledge, we must get rid of the body and contemplate things with the soul [Plato]
14. Science / D. Explanation / 2. Types of Explanation / g. Causal explanations
To investigate the causes of things, study what is best for them [Plato]
15. Nature of Minds / A. Nature of Mind / 8. Brain
Do we think and experience with blood, air or fire, or could it be our brain? [Plato]
16. Persons / D. Continuity of the Self / 1. Identity and the Self
One soul can't be more or less of a soul than another [Plato]
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]
22. Metaethics / C. The Good / 3. Pleasure / e. Role of pleasure
It is a mistake to think that the most violent pleasure or pain is therefore the truest reality [Plato]
23. Ethics / C. Virtue Theory / 4. External Goods / c. Wealth
War aims at the acquisition of wealth, because we are enslaved to the body [Plato]
26. Natural Theory / C. Causation / 2. Types of cause
Fancy being unable to distinguish a cause from its necessary background conditions! [Plato]
27. Natural Reality / E. Cosmology / 1. Cosmology
If the Earth is spherical and in the centre, it is kept in place by universal symmetry, not by force [Plato]
29. Religion / D. Religious Issues / 2. Immortality / a. Immortality
Whether the soul pre-exists our body depends on whether it contains the ultimate standard of reality [Plato]