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All the ideas for 'Introducing the Philosophy of Mathematics', 'Logic (Encyclopedia I)' and 'Humean metaphysics vs metaphysics of Powers'

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88 ideas

1. Philosophy / D. Nature of Philosophy / 5. Aims of Philosophy / b. Philosophy as transcendent
True philosophy aims at absolute unity, while our understanding sees only separation [Hegel]
1. Philosophy / D. Nature of Philosophy / 6. Hopes for Philosophy
Free thinking has no presuppositions [Hegel]
1. Philosophy / E. Nature of Metaphysics / 1. Nature of Metaphysics
The ideal of reason is the unification of abstract identity (or 'concept') and being [Hegel]
1. Philosophy / E. Nature of Metaphysics / 2. Possibility of Metaphysics
Older metaphysics naively assumed that thought grasped things in themselves [Hegel]
1. Philosophy / E. Nature of Metaphysics / 6. Metaphysics as Conceptual
Logic is metaphysics, the science of things grasped in thoughts [Hegel]
1. Philosophy / H. Continental Philosophy / 1. Continental Philosophy
We must break up the rigidity that our understanding has imposed [Hegel]
2. Reason / A. Nature of Reason / 3. Pure Reason
Let thought follow its own course, and don't interfere [Hegel]
2. Reason / A. Nature of Reason / 5. Objectivity
Categories create objective experience, but are too conditioned by things to actually grasp them [Hegel]
2. Reason / B. Laws of Thought / 3. Non-Contradiction
If truth is just non-contradiction, we must take care that our basic concepts aren't contradictory [Hegel]
2. Reason / C. Styles of Reason / 1. Dialectic
Older metaphysics became dogmatic, by assuming opposed assertions must be true and false [Hegel]
Dialectic is seen in popular proverbs like 'pride comes before a fall' [Hegel]
Dialectic is the moving soul of scientific progression, the principle which binds science together [Hegel]
Socratic dialectic is subjective, but Plato made it freely scientific and objective [Hegel]
2. Reason / D. Definition / 8. Impredicative Definition
An 'impredicative' definition seems circular, because it uses the term being defined [Friend]
2. Reason / D. Definition / 10. Stipulative Definition
Classical definitions attempt to refer, but intuitionist/constructivist definitions actually create objects [Friend]
2. Reason / E. Argument / 5. Reductio ad Absurdum
Reductio ad absurdum proves an idea by showing that its denial produces contradiction [Friend]
3. Truth / A. Truth Problems / 2. Defining Truth
Superficial truth is knowing how something is, which is consciousness of bare correctness [Hegel]
3. Truth / A. Truth Problems / 5. Truth Bearers
In Hegel's logic it is concepts (rather than judgements or propositions) which are true or false [Hegel, by Scruton]
3. Truth / A. Truth Problems / 7. Falsehood
In the deeper sense of truth, to be untrue resembles being bad; badness is untrue to a thing's nature [Hegel]
3. Truth / A. Truth Problems / 8. Subjective Truth
Anti-realists see truth as our servant, and epistemically contrained [Friend]
3. Truth / C. Correspondence Truth / 1. Correspondence Truth
The deeper sense of truth is a thing matching the idea of what it ought to be [Hegel]
4. Formal Logic / B. Propositional Logic PL / 3. Truth Tables
In classical/realist logic the connectives are defined by truth-tables [Friend]
4. Formal Logic / E. Nonclassical Logics / 2. Intuitionist Logic
Double negation elimination is not valid in intuitionist logic [Friend]
4. Formal Logic / E. Nonclassical Logics / 6. Free Logic
Free logic was developed for fictional or non-existent objects [Friend]
4. Formal Logic / F. Set Theory ST / 2. Mechanics of Set Theory / b. Terminology of ST
A 'proper subset' of A contains only members of A, but not all of them [Friend]
A 'powerset' is all the subsets of a set [Friend]
4. Formal Logic / F. Set Theory ST / 3. Types of Set / b. Empty (Null) Set
Set theory makes a minimum ontological claim, that the empty set exists [Friend]
4. Formal Logic / F. Set Theory ST / 3. Types of Set / d. Infinite Sets
Infinite sets correspond one-to-one with a subset [Friend]
4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / a. Axioms for sets
Major set theories differ in their axioms, and also over the additional axioms of choice and infinity [Friend]
5. Theory of Logic / D. Assumptions for Logic / 2. Excluded Middle
Excluded middle is the maxim of definite understanding, but just produces contradictions [Hegel]
The law of excluded middle is syntactic; it just says A or not-A, not whether they are true or false [Friend]
5. Theory of Logic / G. Quantification / 7. Unorthodox Quantification
Intuitionists read the universal quantifier as "we have a procedure for checking every..." [Friend]
5. Theory of Logic / L. Paradox / 3. Antinomies
The idea that contradiction is essential to rational understanding is a key modern idea [Hegel]
Tenderness for the world solves the antinomies; contradiction is in our reason, not in the essence of the world [Hegel]
Antinomies are not just in four objects, but in all objects, all representations, all objects and all ideas [Hegel]
5. Theory of Logic / L. Paradox / 5. Paradoxes in Set Theory / a. Set theory paradoxes
Paradoxes can be solved by talking more loosely of 'classes' instead of 'sets' [Friend]
5. Theory of Logic / L. Paradox / 5. Paradoxes in Set Theory / c. Burali-Forti's paradox
The Burali-Forti paradox asks whether the set of all ordinals is itself an ordinal [Friend]
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / b. Types of number
The 'integers' are the positive and negative natural numbers, plus zero [Friend]
The 'rational' numbers are those representable as fractions [Friend]
A number is 'irrational' if it cannot be represented as a fraction [Friend]
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / c. Priority of numbers
The natural numbers are primitive, and the ordinals are up one level of abstraction [Friend]
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / f. Cardinal numbers
Cardinal numbers answer 'how many?', with the order being irrelevant [Friend]
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / g. Real numbers
The 'real' numbers (rationals and irrationals combined) is the Continuum, which has no gaps [Friend]
6. Mathematics / A. Nature of Mathematics / 5. The Infinite / h. Ordinal infinity
Raising omega to successive powers of omega reveal an infinity of infinities [Friend]
The first limit ordinal is omega (greater, but without predecessor), and the second is twice-omega [Friend]
6. Mathematics / A. Nature of Mathematics / 5. The Infinite / j. Infinite divisibility
Between any two rational numbers there is an infinite number of rational numbers [Friend]
6. Mathematics / B. Foundations for Mathematics / 1. Foundations for Mathematics
Is mathematics based on sets, types, categories, models or topology? [Friend]
6. Mathematics / B. Foundations for Mathematics / 6. Mathematics as Set Theory / a. Mathematics is set theory
Most mathematical theories can be translated into the language of set theory [Friend]
6. Mathematics / B. Foundations for Mathematics / 7. Mathematical Structuralism / a. Structuralism
The number 8 in isolation from the other numbers is of no interest [Friend]
In structuralism the number 8 is not quite the same in different structures, only equivalent [Friend]
6. Mathematics / B. Foundations for Mathematics / 7. Mathematical Structuralism / b. Varieties of structuralism
Are structures 'ante rem' (before reality), or are they 'in re' (grounded in physics)? [Friend]
6. Mathematics / B. Foundations for Mathematics / 7. Mathematical Structuralism / c. Nominalist structuralism
Structuralist says maths concerns concepts about base objects, not base objects themselves [Friend]
Structuralism focuses on relations, predicates and functions, with objects being inessential [Friend]
6. Mathematics / B. Foundations for Mathematics / 7. Mathematical Structuralism / d. Platonist structuralism
'In re' structuralism says that the process of abstraction is pattern-spotting [Friend]
6. Mathematics / C. Sources of Mathematics / 1. Mathematical Platonism / b. Against mathematical platonism
The big problem for platonists is epistemic: how do we perceive, intuit, know or detect mathematical facts? [Friend]
6. Mathematics / C. Sources of Mathematics / 4. Mathematical Empiricism / b. Indispensability of mathematics
Mathematics should be treated as true whenever it is indispensable to our best physical theory [Friend]
6. Mathematics / C. Sources of Mathematics / 7. Formalism
Formalism is unconstrained, so cannot indicate importance, or directions for research [Friend]
6. Mathematics / C. Sources of Mathematics / 10. Constructivism / a. Constructivism
Constructivism rejects too much mathematics [Friend]
6. Mathematics / C. Sources of Mathematics / 10. Constructivism / b. Intuitionism
Intuitionists typically retain bivalence but reject the law of excluded middle [Friend]
7. Existence / E. Categories / 1. Categories
Even simple propositions about sensations are filled with categories [Hegel]
Thought about particulars is done entirely through categories [Hegel]
9. Objects / A. Existence of Objects / 2. Abstract Objects / a. Nature of abstracta
Structuralists call a mathematical 'object' simply a 'place in a structure' [Friend]
9. Objects / B. Unity of Objects / 2. Substance / a. Substance
The one substance is formless without the mediation of dialectical concepts [Hegel]
9. Objects / D. Essence of Objects / 6. Essence as Unifier
Essence is the essential self-positing unity of immediacy and mediation [Hegel]
9. Objects / D. Essence of Objects / 14. Knowledge of Essences
Real cognition grasps a thing from within itself, and is not satisfied with mere predicates [Hegel]
11. Knowledge Aims / B. Certain Knowledge / 4. The Cogito
The Cogito is at the very centre of the entire concern of modern philosophy [Hegel]
11. Knowledge Aims / C. Knowing Reality / 3. Idealism / d. Absolute idealism
Existence is just a set of relationships [Hegel]
12. Knowledge Sources / B. Perception / 1. Perception
The sensible is distinguished from thought by being about singular things [Hegel]
12. Knowledge Sources / C. Rationalism / 1. Rationalism
Sense perception is secondary and dependent, while thought is independent and primitive [Hegel]
12. Knowledge Sources / D. Empiricism / 1. Empiricism
Empiricism made particular knowledge possible, and blocked wild claims [Hegel]
Empiricism contains the important idea that we should see knowledge for ourselves, and be part of it [Hegel]
12. Knowledge Sources / D. Empiricism / 5. Empiricism Critique
Empiricism unknowingly contains and uses a metaphysic, which underlies its categories [Hegel]
Empiricism of the finite denies the supersensible, and can only think with formal abstraction [Hegel]
The Humean view stops us thinking about perception, and finding universals and necessities in it [Hegel]
13. Knowledge Criteria / D. Scepticism / 2. Types of Scepticism
Humean scepticism, unlike ancient Greek scepticism, accepts the truth of experience as basic [Hegel]
16. Persons / F. Free Will / 7. Compatibilism
In abstraction, beyond finitude, freedom and necessity must exist together [Hegel]
17. Mind and Body / E. Mind as Physical / 2. Reduction of Mind
Studying biology presumes the laws of chemistry, and it could never contradict them [Friend]
18. Thought / A. Modes of Thought / 1. Thought
The act of thinking is the bringing forth of universals [Hegel]
18. Thought / B. Mechanics of Thought / 2. Categories of Understanding
Hegel's system has a vast number of basic concepts [Hegel, by Moore,AW]
18. Thought / D. Concepts / 1. Concepts / a. Nature of concepts
We don't think with concepts - we think the concepts [Hegel]
Active thought about objects produces the universal, which is what is true and essential of it [Hegel]
Concepts can be presented extensionally (as objects) or intensionally (as a characterization) [Friend]
26. Natural Theory / C. Causation / 1. Causation
Old metaphysics tried to grasp eternal truths through causal events, which is impossible [Hegel]
27. Natural Reality / D. Time / 2. Passage of Time / g. Time's arrow
Causation is the power of one property to produce another, and this gives time its direction [Esfeld]
28. God / A. Divine Nature / 2. Divine Nature
The older conception of God was emptied of human features, to make it worthy of the Infinite [Hegel]
God is the absolute thing, and also the absolute person [Hegel]
If God is the abstract of Supremely Real Essence, then God is a mere Beyond, and unknowable [Hegel]
28. God / B. Proving God / 2. Proofs of Reason / a. Ontological Proof
We establish unification of the Ideal by the ontological proof, deriving being from abstraction of thinking [Hegel]