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All the ideas for 'Logic (Encyclopedia I)', 'De modo distinguendi phaenomena' and 'works'

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91 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
Dialectic is the moving soul of scientific progression, the principle which binds science together [Hegel]
Dialectic is seen in popular proverbs like 'pride comes before a fall' [Hegel]
Socratic dialectic is subjective, but Plato made it freely scientific and objective [Hegel]
Older metaphysics became dogmatic, by assuming opposed assertions must be true and false [Hegel]
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 / 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 / F. Set Theory ST / 1. Set Theory
Trying to represent curves, we study arbitrary functions, leading to the ordinals, which produces set theory [Cantor, by Lavine]
4. Formal Logic / F. Set Theory ST / 2. Mechanics of Set Theory / c. Basic theorems of ST
Cantor's Theorem: for any set x, its power set P(x) has more members than x [Cantor, by Hart,WD]
Cantor proved that all sets have more subsets than they have members [Cantor, by Bostock]
4. Formal Logic / F. Set Theory ST / 3. Types of Set / c. Unit (Singleton) Sets
If a set is 'a many thought of as one', beginners should protest against singleton sets [Cantor, by Lewis]
4. Formal Logic / F. Set Theory ST / 3. Types of Set / d. Infinite Sets
The continuum is the powerset of the integers, which moves up a level [Cantor, by Clegg]
Cantor showed that supposed contradictions in infinity were just a lack of clarity [Cantor, by Potter]
4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / d. Axiom of Unions III
The Axiom of Union dates from 1899, and seems fairly obvious [Cantor, by Maddy]
4. Formal Logic / F. Set Theory ST / 5. Conceptions of Set / b. Combinatorial sets
Cantor's sets were just collections, but Dedekind's were containers [Cantor, by Oliver/Smiley]
5. Theory of Logic / D. Assumptions for Logic / 2. Excluded Middle
Excluded middle is the maxim of definite understanding, but just produces contradictions [Hegel]
5. Theory of Logic / K. Features of Logics / 8. Enumerability
There are infinite sets that are not enumerable [Cantor, by Smith,P]
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 / b. Cantor's paradox
Cantor's Paradox: the power set of the universe must be bigger than the universe, yet a subset of it [Cantor, by Hart,WD]
5. Theory of Logic / L. Paradox / 5. Paradoxes in Set Theory / e. Mirimanoff's paradox
The powerset of all the cardinal numbers is required to be greater than itself [Cantor, by Friend]
6. Mathematics / A. Nature of Mathematics / 1. Mathematics
Cantor named the third realm between the finite and the Absolute the 'transfinite' [Cantor, by Lavine]
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / b. Types of number
Cantor proved the points on a plane are in one-to-one correspondence to the points on a line [Cantor, by Lavine]
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / c. Priority of numbers
Cantor took the ordinal numbers to be primary [Cantor, by Tait]
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / d. Natural numbers
Cantor presented the totality of natural numbers as finite, not infinite [Cantor, by Mayberry]
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / e. Ordinal numbers
Cantor introduced the distinction between cardinals and ordinals [Cantor, by Tait]
Cantor showed that ordinals are more basic than cardinals [Cantor, by Dummett]
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / f. Cardinal numbers
A cardinal is an abstraction, from the nature of a set's elements, and from their order [Cantor]
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / g. Real numbers
Cantor tried to prove points on a line matched naturals or reals - but nothing in between [Cantor, by Lavine]
Cantor's diagonal argument proved you can't list all decimal numbers between 0 and 1 [Cantor, by Read]
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / h. Reals from Cauchy
A real is associated with an infinite set of infinite Cauchy sequences of rationals [Cantor, by Lavine]
Irrational numbers are the limits of Cauchy sequences of rational numbers [Cantor, by Lavine]
6. Mathematics / A. Nature of Mathematics / 5. The Infinite / a. The Infinite
Irrationals and the Dedekind Cut implied infinite classes, but they seemed to have logical difficulties [Cantor, by Lavine]
It was Cantor's diagonal argument which revealed infinities greater than that of the real numbers [Cantor, by Lavine]
6. Mathematics / A. Nature of Mathematics / 5. The Infinite / d. Actual infinite
Cantor proposes that there won't be a potential infinity if there is no actual infinity [Cantor, by Hart,WD]
6. Mathematics / A. Nature of Mathematics / 5. The Infinite / f. Uncountable infinities
The naturals won't map onto the reals, so there are different sizes of infinity [Cantor, by George/Velleman]
6. Mathematics / A. Nature of Mathematics / 5. The Infinite / g. Continuum Hypothesis
CH: An infinite set of reals corresponds 1-1 either to the naturals or to the reals [Cantor, by Koellner]
The Continuum Hypothesis says there are no sets between the natural numbers and reals [Cantor, by Shapiro]
Cantor: there is no size between naturals and reals, or between a set and its power set [Cantor, by Hart,WD]
Cantor's Continuum Hypothesis says there is a gap between the natural and the real numbers [Cantor, by Horsten]
Continuum Hypothesis: there are no sets between N and P(N) [Cantor, by Wolf,RS]
Continuum Hypothesis: no cardinal greater than aleph-null but less than cardinality of the continuum [Cantor, by Chihara]
6. Mathematics / A. Nature of Mathematics / 5. The Infinite / h. Ordinal infinity
Cantor's theory concerns collections which can be counted, using the ordinals [Cantor, by Lavine]
Cantor extended ordinals into the transfinite, and they can thus measure infinite cardinalities [Cantor, by Maddy]
6. Mathematics / A. Nature of Mathematics / 5. The Infinite / i. Cardinal infinity
Cardinality strictly concerns one-one correspondence, to test infinite sameness of size [Cantor, by Maddy]
6. Mathematics / B. Foundations for Mathematics / 5. Definitions of Number / e. Caesar problem
Property extensions outstrip objects, so shortage of objects caused the Caesar problem [Cantor, by Shapiro]
6. Mathematics / B. Foundations for Mathematics / 6. Mathematics as Set Theory / a. Mathematics is set theory
Pure mathematics is pure set theory [Cantor]
6. Mathematics / C. Sources of Mathematics / 4. Mathematical Empiricism / a. Mathematical empiricism
Cantor says that maths originates only by abstraction from objects [Cantor, by Frege]
7. Existence / D. Theories of Reality / 2. Realism
If experience is just a dream, it is still real enough if critical reason is never deceived [Leibniz]
The strongest criterion that phenomena show reality is success in prediction [Leibniz]
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 / 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 / B. Perception / 2. Qualities in Perception / e. Primary/secondary critique
Light, heat and colour are apparent qualities, and so are motion, figure and extension [Leibniz]
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]
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]
Infinities expand the bounds of the conceivable; we explore concepts to explore conceivability [Cantor, by Friend]
18. Thought / E. Abstraction / 2. Abstracta by Selection
Cantor says (vaguely) that we abstract numbers from equal sized sets [Hart,WD on Cantor]
26. Natural Theory / C. Causation / 1. Causation
Old metaphysics tried to grasp eternal truths through causal events, which is impossible [Hegel]
27. Natural Reality / C. Space / 3. Points in Space
Cantor proved that three dimensions have the same number of points as one dimension [Cantor, by Clegg]
28. God / A. Divine Nature / 2. Divine Nature
If God is the abstract of Supremely Real Essence, then God is a mere Beyond, and unknowable [Hegel]
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]
Only God is absolutely infinite [Cantor, by Hart,WD]
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]