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All the ideas for 'Science of Logic', 'fragments/reports' and 'Introduction to Mathematical Philosophy'

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84 ideas

1. Philosophy / E. Nature of Metaphysics / 6. Metaphysics as Conceptual
If we start with indeterminate being, we arrive at being and nothing as a united pair [Hegel, by Houlgate]
Thought about being leads to a string of other concepts, like becoming, quantity, specificity, causality... [Hegel, by Houlgate]
We must start with absolute abstraction, with no presuppositions, so we start with pure being [Hegel]
1. Philosophy / F. Analytic Philosophy / 5. Linguistic Analysis
'Socrates is human' expresses predication, and 'Socrates is a man' expresses identity [Russell]
2. Reason / A. Nature of Reason / 5. Objectivity
Objectivity is not by correspondence, but by the historical determined necessity of Geist [Hegel, by Pinkard]
2. Reason / B. Laws of Thought / 3. Non-Contradiction
Being and nothing are the same and not the same, which is the identity of identity and non-identity [Hegel]
The so-called world is filled with contradiction [Hegel]
2. Reason / C. Styles of Reason / 1. Dialectic
Dialectic is the instability of thoughts generating their opposite, and then new more complex thoughts [Hegel, by Houlgate]
Hegel's dialectic is not thesis-antithesis-synthesis, but usually negation of negation of the negation [Hegel, by Moore,AW]
2. Reason / D. Definition / 3. Types of Definition
A definition by 'extension' enumerates items, and one by 'intension' gives a defining property [Russell]
2. Reason / F. Fallacies / 8. Category Mistake / a. Category mistakes
The sentence 'procrastination drinks quadruplicity' is meaningless, rather than false [Russell, by Orenstein]
3. Truth / F. Semantic Truth / 1. Tarski's Truth / b. Satisfaction and truth
An argument 'satisfies' a function φx if φa is true [Russell]
4. Formal Logic / A. Syllogistic Logic / 2. Syllogistic Logic
The Darapti syllogism is fallacious: All M is S, all M is P, so some S is P' - but if there is no M? [Russell]
4. Formal Logic / F. Set Theory ST / 3. Types of Set / d. Infinite Sets
We can enumerate finite classes, but an intensional definition is needed for infinite classes [Russell]
4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / b. Axiom of Extensionality I
Members define a unique class, whereas defining characteristics are numerous [Russell]
4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / f. Axiom of Infinity V
We may assume that there are infinite collections, as there is no logical reason against them [Russell]
Infinity says 'for any inductive cardinal, there is a class having that many terms' [Russell]
4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / j. Axiom of Choice IX
The British parliament has one representative selected from each constituency [Russell]
Choice shows that if any two cardinals are not equal, one must be the greater [Russell]
Choice is equivalent to the proposition that every class is well-ordered [Russell]
We can pick all the right or left boots, but socks need Choice to insure the representative class [Russell]
4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / p. Axiom of Reducibility
Reducibility: a family of functions is equivalent to a single type of function [Russell]
4. Formal Logic / F. Set Theory ST / 5. Conceptions of Set / c. Logical sets
Propositions about classes can be reduced to propositions about their defining functions [Russell]
4. Formal Logic / F. Set Theory ST / 7. Natural Sets
Russell's proposal was that only meaningful predicates have sets as their extensions [Russell, by Orenstein]
4. Formal Logic / F. Set Theory ST / 8. Critique of Set Theory
Classes are logical fictions, and are not part of the ultimate furniture of the world [Russell]
5. Theory of Logic / A. Overview of Logic / 4. Pure Logic
All the propositions of logic are completely general [Russell]
5. Theory of Logic / A. Overview of Logic / 8. Logic of Mathematics
In modern times, logic has become mathematical, and mathematics has become logical [Russell]
5. Theory of Logic / C. Ontology of Logic / 1. Ontology of Logic
Logic can be known a priori, without study of the actual world [Russell]
Logic is concerned with the real world just as truly as zoology [Russell]
Logic can only assert hypothetical existence [Russell]
5. Theory of Logic / F. Referring in Logic / 1. Naming / b. Names as descriptive
Russell admitted that even names could also be used as descriptions [Russell, by Bach]
Asking 'Did Homer exist?' is employing an abbreviated description [Russell]
Names are really descriptions, except for a few words like 'this' and 'that' [Russell]
5. Theory of Logic / F. Referring in Logic / 1. Naming / f. Names eliminated
The only genuine proper names are 'this' and 'that' [Russell]
5. Theory of Logic / F. Referring in Logic / 2. Descriptions / a. Descriptions
'I met a unicorn' is meaningful, and so is 'unicorn', but 'a unicorn' is not [Russell]
5. Theory of Logic / L. Paradox / 1. Paradox
If you know your father, but don't recognise your father veiled, you know and don't know the same person [Eubulides, by Dancy,R]
5. Theory of Logic / L. Paradox / 6. Paradoxes in Language / a. The Liar paradox
If you say truly that you are lying, you are lying [Eubulides, by Dancy,R]
5. Theory of Logic / L. Paradox / 6. Paradoxes in Language / b. The Heap paradox ('Sorites')
Removing one grain doesn't destroy a heap, so a heap can't be destroyed [Eubulides, by Dancy,R]
6. Mathematics / A. Nature of Mathematics / 2. Geometry
If straight lines were like ratios they might intersect at a 'gap', and have no point in common [Russell]
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / b. Types of number
New numbers solve problems: negatives for subtraction, fractions for division, complex for equations [Russell]
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / c. Priority of numbers
Could a number just be something which occurs in a progression? [Russell, by Hart,WD]
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / i. Reals from cuts
A series can be 'Cut' in two, where the lower class has no maximum, the upper no minimum [Russell]
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / j. Complex numbers
A complex number is simply an ordered couple of real numbers [Russell]
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / m. One
Discovering that 1 is a number was difficult [Russell]
6. Mathematics / A. Nature of Mathematics / 4. Using Numbers / c. Counting procedure
Numbers are needed for counting, so they need a meaning, and not just formal properties [Russell]
6. Mathematics / A. Nature of Mathematics / 4. Using Numbers / f. Arithmetic
The formal laws of arithmetic are the Commutative, the Associative and the Distributive [Russell]
6. Mathematics / A. Nature of Mathematics / 5. The Infinite / a. The Infinite
Infinity and continuity used to be philosophy, but are now mathematics [Russell]
6. Mathematics / B. Foundations for Mathematics / 4. Axioms for Number / a. Axioms for numbers
The definition of order needs a transitive relation, to leap over infinite intermediate terms [Russell]
6. Mathematics / B. Foundations for Mathematics / 4. Axioms for Number / d. Peano arithmetic
Any founded, non-repeating series all reachable in steps will satisfy Peano's axioms [Russell]
'0', 'number' and 'successor' cannot be defined by Peano's axioms [Russell]
6. Mathematics / B. Foundations for Mathematics / 5. Definitions of Number / d. Hume's Principle
A number is something which characterises collections of the same size [Russell]
6. Mathematics / B. Foundations for Mathematics / 7. Mathematical Structuralism / a. Structuralism
What matters is the logical interrelation of mathematical terms, not their intrinsic nature [Russell]
6. Mathematics / C. Sources of Mathematics / 5. Numbers as Adjectival
Maybe numbers are adjectives, since 'ten men' grammatically resembles 'white men' [Russell]
6. Mathematics / C. Sources of Mathematics / 6. Logicism / a. Early logicism
For Russell, numbers are sets of equivalent sets [Russell, by Benacerraf]
6. Mathematics / C. Sources of Mathematics / 10. Constructivism / e. Psychologism
There is always something psychological about inference [Russell]
7. Existence / A. Nature of Existence / 1. Nature of Existence
Existence can only be asserted of something described, not of something named [Russell]
7. Existence / A. Nature of Existence / 3. Being / d. Non-being
To grasp an existence, we must consider its non-existence [Hegel, by Houlgate]
Nothing exists, as thinkable and expressible [Hegel]
7. Existence / A. Nature of Existence / 3. Being / e. Being and nothing
Thinking of nothing is not the same as simply not thinking [Hegel, by Houlgate]
7. Existence / C. Structure of Existence / 1. Grounding / a. Nature of grounding
The ground of a thing is not another thing, but the first thing's substance or rational concept [Hegel, by Houlgate]
7. Existence / D. Theories of Reality / 2. Realism
Kant's thing-in-itself is just an abstraction from our knowledge; things only exist for us [Hegel, by Bowie]
Hegel believe that the genuine categories reveal things in themselves [Hegel, by Houlgate]
7. Existence / D. Theories of Reality / 7. Fictionalism
Classes are logical fictions, made from defining characteristics [Russell]
8. Modes of Existence / A. Relations / 2. Internal Relations
The nature of each category relates itself to another [Hegel]
8. Modes of Existence / A. Relations / 4. Formal Relations / a. Types of relation
If a relation is symmetrical and transitive, it has to be reflexive [Russell]
'Asymmetry' is incompatible with its converse; a is husband of b, so b can't be husband of a [Russell]
9. Objects / D. Essence of Objects / 3. Individual Essences
The essence of individuality is beyond description, and hence irrelevant to science [Russell]
10. Modality / B. Possibility / 8. Conditionals / c. Truth-function conditionals
Inferring q from p only needs p to be true, and 'not-p or q' to be true [Russell]
All forms of implication are expressible as truth-functions [Russell]
10. Modality / E. Possible worlds / 1. Possible Worlds / a. Possible worlds
If something is true in all possible worlds then it is logically necessary [Russell]
11. Knowledge Aims / B. Certain Knowledge / 1. Certainty
In absolute knowing, the gap between object and oneself closes, producing certainty [Hegel]
11. Knowledge Aims / C. Knowing Reality / 3. Idealism / d. Absolute idealism
The 'absolute idea' is when all the contradictions are exhausted [Hegel, by Bowie]
Hegel, unlike Kant, said how things appear is the same as how things are [Hegel, by Moore,AW]
Hegel's non-subjective idealism is the unity of subjective and objective viewpoints [Hegel, by Pinkard]
Hegel claimed his system was about the world, but it only mapped conceptual interdependence [Pinkard on Hegel]
Authentic thinking and reality have the same content [Hegel]
The Absolute is the primitive system of concepts which are actualised [Hegel, by Gardner]
The absolute idea is being, imperishable life, self-knowing truth, and all truth [Hegel]
The absolute idea is the great unity of the infinite system of concepts [Hegel, by Moore,AW]
13. Knowledge Criteria / B. Internal Justification / 5. Coherentism / a. Coherence as justification
Hegel's 'absolute idea' is the interdependence of all truths to justify any of them [Hegel, by Bowie]
14. Science / B. Scientific Theories / 1. Scientific Theory
Mathematically expressed propositions are true of the world, but how to interpret them? [Russell]
18. Thought / D. Concepts / 1. Concepts / a. Nature of concepts
Every concept depends on the counter-concepts of what it is not [Hegel, by Bowie]
19. Language / D. Propositions / 1. Propositions
Propositions are mainly verbal expressions of true or false, and perhaps also symbolic thoughts [Russell]
19. Language / E. Analyticity / 4. Analytic/Synthetic Critique
When we explicate the category of being, we watch a new category emerge [Hegel, by Houlgate]