Ideas from 'Critique of Pure Reason' by Immanuel Kant [1781], by Theme Structure

[found in 'Critique of Pure Reason' by Kant,Immanuel (ed/tr Guyer,P /Wood,A W) [CUO 1998,0-521-65729-6]].

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1. Philosophy / A. Wisdom / 1. Nature of Wisdom
Cleverness is shown in knowing what can reasonably be asked
1. Philosophy / D. Nature of Philosophy / 4. Aims of Philosophy / e. Philosophy as reason
Reason is only interested in knowledge, actions and hopes
1. Philosophy / D. Nature of Philosophy / 6. Despair over Philosophy
In ordinary life the highest philosophy is no better than common understanding
1. Philosophy / E. Nature of Metaphysics / 2. Possibility of Metaphysics
Kant turned metaphysics into epistemology, ignoring Aristotle's 'being qua being'
The voyage of reason may go only as far as the coastline of experience reaches
You just can't stop metaphysical speculation, in any mature mind
1. Philosophy / E. Nature of Metaphysics / 4. Metaphysics beyond Science
Kant showed that theoretical reason cannot give anwers to speculative metaphysics
A priori metaphysics is fond of basic unchanging entities like God, the soul, Forms, atoms…
A dove cutting through the air, might think it could fly better in airless space (which Plato attempted)
1. Philosophy / E. Nature of Metaphysics / 6. Against Metaphysics
Kant exposed the illusions of reason in the Transcendental Dialectic
1. Philosophy / F. Analytic Philosophy / 1. Analysis
Analysis is becoming self-conscious about our concepts
1. Philosophy / F. Analytic Philosophy / 2. Conceptual Analysis
Our reason mostly analyses concepts we already have of objects
Analysis of our concepts is merely a preparation for proper a priori metaphysics
2. Reason / A. Nature of Reason / 1. On Reason
If I know the earth is a sphere, and I am on it, I can work out its area from a small part
The boundaries of reason can only be determined a priori
In reason things can only begin if they are voluntary
2. Reason / A. Nature of Reason / 3. Pure Reason
Pure reason exists outside of time
Reason hates to be limited in its speculations
Pure reason is only concerned with itself because it deals with understandings, not objects
Pure reason deals with concepts in the understanding, not with objects
2. Reason / A. Nature of Reason / 4. Aims of Reason
All objections are dogmatic (against propositions), or critical (against proofs), or sceptical
Reason keeps asking why until explanation is complete
2. Reason / B. Laws of Thought / 2. Sufficient Reason
The principle of sufficient reason is the ground of possible experience in time
Proof of the principle of sufficient reason cannot be found
2. Reason / C. Styles of Reason / 1. Dialectic
The free dialectic opposition of arguments is an invaluable part of the sceptical method
2. Reason / D. Definition / 2. Aims of Definition
Definitions exhibit the exhaustive concept of a thing within its boundaries
2. Reason / D. Definition / 12. Against Definition
No a priori concept can be defined
2. Reason / E. Argument / 2. Transcendental Argument
Transcendental ideas require unity of the subject, conditions of appearance, and objects of thought
2. Reason / E. Argument / 3. Analogy
Philosophical examples rarely fit rules properly, and lead to inflexibility
3. Truth / C. Correspondence Truth / 1. Correspondence Truth
We must presuppose that truth is agreement of cognition with its objects
4. Formal Logic / B. Propositional Logic PL / 2. Tools of Propositional Logic / e. Axioms of PL
Philosophy has no axioms, as it is just rational cognition of concepts
5. Theory of Logic / A. Overview of Logic / 1. Overview of Logic
Logic has precise boundaries, and is the formal rules for all thinking
5. Theory of Logic / I. Semantics of Logic / 2. Formal Truth
There must be a general content-free account of truth in the rules of logic
6. Mathematics / A. Nature of Mathematics / 4. The Infinite / c. Potential infinite
Kant only accepts potential infinity, not actual infinity
6. Mathematics / A. Nature of Mathematics / 5. Geometry
Geometry studies the Euclidean space that dictates how we perceive things
Geometrical truth comes from a general schema abstracted from a particular object
Geometry would just be an idle game without its connection to our intuition
6. Mathematics / B. Foundations for Mathematics / 2. Axioms for Geometry
Euclid's could be the only viable geometry, if rejection of the parallel line postulate doesn't lead to a contradiction
6. Mathematics / B. Foundations for Mathematics / 3. Axioms for Number / a. Axioms for numbers
Kant suggested that arithmetic has no axioms
Axioms ought to be synthetic a priori propositions
6. Mathematics / C. Sources of Mathematics / 4. Mathematical Empiricism / a. Mathematical empiricism
Maths is a priori, but without its relation to empirical objects it is meaningless
6. Mathematics / C. Sources of Mathematics / 6. Logicism / d. Logicism critique
If 7+5=12 is analytic, then an infinity of other ways to reach 12 have to be analytic
7. Existence / A. Nature of Existence / 1. Nature of Existence
Saying a thing 'is' adds nothing to it - otherwise if my concept exists, it isn't the same as my concept
7. Existence / D. Theories of Reality / 1. Realism
Kant is read as the phenomena being 'contrained' by the noumenon, or 'free-floating'
7. Existence / D. Theories of Reality / 3. Anti-realism
Without the subject or the senses, space and time vanish, as their appearances disappear
7. Existence / E. Categories / 1. Categories
Categories are necessary, so can't be implanted in us to agree with natural laws
7. Existence / E. Categories / 2. Categorisation
Does Kant say the mind imposes categories, or that it restricts us to them?
8. Modes of Existence / C. Powers and Dispositions / 7. Against Powers
Kant claims causal powers are relational rather than intrinsic
8. Modes of Existence / D. Universals / 6. Platonic Forms / d. Forms critiques
Plato's Forms not only do not come from the senses, but they are beyond possibility of sensing
9. Objects / A. Existence of Objects / 1. Physical Objects
Objects in themselves are not known to us at all
9. Objects / B. Unity of Objects / 2. Substance / a. Substance
A substance could exist as a subject, but not as a mere predicate
9. Objects / B. Unity of Objects / 2. Substance / d. Substance defined
Substance must exist, as the persisting substratum of the process of change
9. Objects / E. Objects over Time / 1. Objects over Time
An a priori principle of persistence anticipates all experience
9. Objects / F. Identity among Objects / 7. Indiscernible Objects
The Identity of Indiscernibles is true of concepts with identical properties, but not of particulars
If we ignore differences between water drops, we still distinguish them by their location
10. Modality / A. Necessity / 1. Types of Modality
Modalities do not augment our concepts; they express their relation to cognition
10. Modality / A. Necessity / 7. Natural Necessity
Natural necessity is the unconditioned necessity of appearances
10. Modality / B. Possibility / 1. Possibility
Is the possible greater than the actual, and the actual greater than the necessary?
A concept is logically possible if non-contradictory (but may not be actually possible)
The analytic mark of possibility is that it does not generate a contradiction
10. Modality / C. Sources of Modality / 4. Necessity from Concepts
Formal experience conditions show what is possible, and general conditions what is necessary
10. Modality / D. Knowledge of Modality / 1. A Priori Necessary
Necessity is always knowable a priori, and what is known a priori is always necessary
For Kant metaphysics must be necessary, so a priori, so can't be justified by experience
Maths must be a priori because it is necessary, and that cannot be derived from experience
11. Knowledge Aims / A. Knowledge / 1. Knowledge
Knowledge begins with intuitions, moves to concepts, and ends with ideas
11. Knowledge Aims / A. Knowledge / 2. Understanding
Reason is distinct from understanding, and is the faculty of rules or principles
Understanding essentially involves singular elements
11. Knowledge Aims / A. Knowledge / 3. Belief / a. Beliefs
Opinion is subjectively and objectively insufficient; belief is subjective but not objective; knowledge is both
11. Knowledge Aims / B. Certain Knowledge / 6. Cogito Critique
'I think therefore I am' is an identity, not an inference (as there is no major premise)
11. Knowledge Aims / C. Knowing Reality / 2. Phenomenalism
There are possible inhabitants of the moon, but they are just possible experiences
11. Knowledge Aims / C. Knowing Reality / 3. Idealism
In Kantian idealism, objects fit understanding, not vice versa
Kant's idealism is a limited idealism based on the viewpoint of empiricism
We cannot know things in themselves, but are confined to appearances
We have proved that bodies are appearances of the outer senses, not things in themselves
12. Knowledge Sources / A. A Priori Knowledge / 1. Nature of the A Priori
One sort of a priori knowledge just analyses given concepts, but another ventures further
A priori knowledge is limited to objects of possible experience
A priori knowledge occurs absolutely independently of all experience
12. Knowledge Sources / A. A Priori Knowledge / 2. Self-Evidence
Experienceless bodies have space; propertyless bodies have substance; this must be seen a priori
12. Knowledge Sources / A. A Priori Knowledge / 4. A Priori as Necessities
The apriori is independent of its sources, and marked by necessity and generality
Two plus two objects make four objects even if experience is impossible, so Kant is wrong
Propositions involving necessity are a priori, and pure a priori if they only derive from other necessities
A priori knowledge is indispensable for the possibility and certainty of experience
12. Knowledge Sources / A. A Priori Knowledge / 5. A Priori Synthetic
Are a priori concepts necessary as a precondition for something to be an object?
We possess synthetic a priori knowledge in our principles which anticipate experience
That a straight line is the shortest is synthetic, as straight does not imply any quantity
7+5=12 is not analytic, because 12 is not contained in 7 or 5 or their combination
That force and counter-force are equal is necessary, and a priori synthetic
The real problem of pure reason is: how are a priori synthetic judgments possible?
Seeing that only one parallel can be drawn to a line through a given point is clearly synthetic a priori
That two lines cannot enclose a space is an intuitive a priori synthetic proposition
We can think of 7 and 5 without 12, but it is still a contradiction to deny 7+5=12
12. Knowledge Sources / A. A Priori Knowledge / 6. A Priori from Reason
Reason contains within itself certain underived concepts and principles
12. Knowledge Sources / A. A Priori Knowledge / 7. A Priori from Convention
If, as Kant says, arithmetic and logic are contributed by us, they could change if we did
12. Knowledge Sources / A. A Priori Knowledge / 8. A Priori as Analytic
No analysis of the sum of seven and five will in itself reveal twelve
12. Knowledge Sources / A. A Priori Knowledge / 9. A Priori from Concepts
For Kant analytic knowledge needs complex concepts, but the a priori can rest on the simple
With large numbers it is obvious that we could never find the sum by analysing the concepts
12. Knowledge Sources / A. A Priori Knowledge / 10. A Priori as Subjective
A priori the understanding can only anticipate possible experiences
12. Knowledge Sources / B. Perception / 2. Qualities in Perception / b. Primary/secondary
We know the shape of a cone from its concept, but we don't know its colour
12. Knowledge Sources / B. Perception / 2. Qualities in Perception / d. Secondary qualities
Colours and tastes are not qualities of things, but alterations of the subject
12. Knowledge Sources / B. Perception / 5. Interpretation
Kant says the cognitive and sensory elements in experience can't be separated
12. Knowledge Sources / C. Rationalism / 1. Rationalism
We cannot represent objects unless we combine concepts with intuitions
12. Knowledge Sources / D. Empiricism / 4. Pro-Empiricism
For Kant, our conceptual scheme is disastrous when it reaches beyond experience
12. Knowledge Sources / D. Empiricism / 5. Empiricism Critique
Understanding has no intuitions, and senses no thought, so knowledge needs their unity
Sensations are a posteriori, but that they come in degrees is known a priori
12. Knowledge Sources / E. Direct Knowledge / 1. Intuition
Kantian intuitions are of particulars, and they give immediate knowledge
13. Knowledge Criteria / B. Internal Justification / 4. Foundationalism / f. Foundationalism critique
A sufficient but general sign of truth cannot possibly be provided
13. Knowledge Criteria / B. Internal Justification / 5. Coherentism / a. Coherence as justification
Kant says knowledge is when our representations sufficiently conform to our concepts
13. Knowledge Criteria / D. Scepticism / 1. Scepticism
Kant thought he had refuted scepticism, but his critics say he is a sceptic, for rejecting reality
13. Knowledge Criteria / D. Scepticism / 2. Types of Scepticism
Hume became a total sceptic, because he believed that reason was a deception
13. Knowledge Criteria / D. Scepticism / 6. Scepticism Critique
Scepticism is the euthanasia of pure reason
Scepticism is absurd in maths, where there are no hidden false assertions
14. Science / A. Basis of Science / 6. Falsification
If a proposition implies any false consequences, then it is false
15. Nature of Minds / A. Nature of Mind / 3. Mental Causation
Freedom and natural necessity do not contradict, as they relate to different conditions
15. Nature of Minds / B. Properties of Minds / 1. Consciousness / f. Higher-order thought
Kant thought that consciousness depends on self-consciousness ('apperception')
15. Nature of Minds / C. Capacities of Minds / 1. Faculties
Reason has logical and transcendental faculties
Judgements which are essentially and strictly universal reveal our faculty of a priori cognition
16. Persons / C. Self-Awareness / 3. Undetectable Self
Self-knowledge can only be inner sensation, and thus appearance
16. Persons / D. Self as Non-Physical / 3. Cartesian Ego
I can express the motion of my body in a single point, but that doesn't mean it is a simple substance
16. Persons / D. Self as Non-Physical / 4. Kantian Ego
To some extent we must view ourselves as noumena
For Kant the self is a purely formal idea, not a substance
Mental representations would not be mine if they did not belong to a unified self-consciousness
I have no cognition of myself as I am, but only as I appear to myself
16. Persons / E. Self as Mind / 3. Psychological Self critique
As balls communicate motion, so substances could communicate consciousness, but not retain identity
16. Persons / F. Self as Body / 1. Role of the Body
We need an account of the self based on rational principles, to avoid materialism
16. Persons / G. Free Will / 1. Free Will / a. Nature of free will
We must assume an absolute causal spontaneity beginning from itself
16. Persons / G. Free Will / 1. Free Will / b. Pro-free will
We must be free, because we can act against our strongest desires
If there is a first beginning, there can be other sequences initiated from nothing
17. Mind and Body / A. Mind-Body Dualism / 1. Dualism
Soul and body connect physically, or by harmony, or by assistance
17. Mind and Body / A. Mind-Body Dualism / 8. Dualism of Mind Critique
Neither materialism nor spiritualism can reveal the separate existence of the soul
Our concept of an incorporeal nature is merely negative
18. Thought / A. Modes of Thought / 1. Thought
A pure concept of the understanding can never become an image
18. Thought / A. Modes of Thought / 6. Rationality
Human reason considers all knowledge as belonging to a possible system
Kantian 'intuition' is the bridge between pure reason and its application to sense experiences
18. Thought / B. Mechanics of Thought / 5. Categories of Understanding
Four categories of concept: Quantity, Quality, Relation and Modality
The categories are objectively valid, because they make experience possible
Categories are concepts that prescribe laws a priori to appearances
18. Thought / D. Concepts / 1. Concepts / a. Concepts
All human cognition is through concepts
Thoughts without content are empty, intuitions without concepts are blind
Reason generates no concepts, but frees them from their link to experience in the understanding
Either experience creates concepts, or concepts make experience possible
18. Thought / D. Concepts / 3. Structure of Concepts / b. Analysis of concepts
Kant implies that concepts have analysable parts
19. Language / F. Analytic/Synthetic / 2. Analytic Propositions
Non-subject/predicate tautologies won't fit Kant's definition of analyticity
How can bachelor 'contain' unmarried man? Are all analytic truths in subject-predicate form?
22. Metaethics / B. Basis of Ethics / 1. Morality
Without God, creation and free will, morality would be empty
22. Metaethics / B. Basis of Ethics / 4. Is/Ought
We cannot derive moral laws from experience, as it is the mother of illusion
23. Ethics / D. Deontological Ethics / 5. Motivation for Duty
Moral blame is based on reason, since a reason is a cause which should have been followed
Moral laws are commands, which must involve promises and threats, which only God could provide
23. Ethics / F. Existentialism / 1. Existentialism
For Kant, essence is mental and is mere idea, and existence is the senses and mere appearance
25. Society / C. Political Doctrines / 6. Liberalism
An obvious idea is a constitution based on maximum mutual freedom for citizens
25. Society / D. Social Rights / 2. Social Freedom / c. Free speech
The existence of reason depends on the freedom of citizens to agree, doubt and veto ideas
26. Natural Theory / A. Heart of Nature / 1. Nature
Kant identifies nature with the scientific picture of it as the realm of law
26. Natural Theory / A. Heart of Nature / 2. Natural Purpose
Reason must assume as necessary that everything in a living organism has a proportionate purpose
26. Natural Theory / B. Concepts of Nature / 1. Basis of Nature
Extension and impenetrability together make the concept of matter
If space and time exist absolutely, we must assume to existence of two pointless non-entities
26. Natural Theory / B. Concepts of Nature / 3. Space / a. Space
Space is an a priori necessary basic intuition, as we cannot imagine its absence
We can't learn of space through experience; experience of space needs its representation
26. Natural Theory / B. Concepts of Nature / 4. Time / a. Time
If time involved succession, we must think of another time in which succession occurs
The three modes of time are persistence, succession and simultaneity
That times cannot be simultaneous is synthetic, so it is known by intuition, not analysis
26. Natural Theory / B. Concepts of Nature / 4. Time / j. Time as subjective
One can never imagine appearances without time, so it is given a priori
26. Natural Theory / C. Causation / 2. Particular Causation / b. Causal relata
A ball denting a pillow seems like simultaneous cause and effect, though time identifies which is cause
26. Natural Theory / C. Causation / 3. General Causation / a. Constant conjunction
Appearances give rules of what usually happens, but cause involves necessity
26. Natural Theory / C. Causation / 3. General Causation / b. Nomological causation
The concept of causality entails laws; random causality is a contradiction
We judge causation by relating events together by some law of nature
Experience is only possible because we subject appearances to causal laws
26. Natural Theory / C. Causation / 3. General Causation / d. Causal necessity
Causation obviously involves necessity, so it cannot just be frequent association
26. Natural Theory / D. Laws of Nature / 8. Scientific Essentialism / b. Scientific necessity
For Kant the laws must be necessary, because contingency would destroy representation
28. God / A. Divine Nature / 5. Divine Morality / b. Euthyphro question
We don't accept duties as coming from God, but assume they are divine because they are duties
28. God / B. Proving God / 1. Proof of God
Only three proofs of God: the physico-theological (evidence), the cosmological (existence), the ontological (a priori)
28. God / C. Proofs of Reason / 2. Ontological Proof critique
If an existential proposition is synthetic, you must be able to cancel its predicate without contradiction
Being is not a real predicate, that adds something to a concept
You add nothing to the concept of God or coins if you say they exist
Existence is merely derived from the word 'is' (rather than being a predicate)
Modern logic says (with Kant) that existence is not a predicate, because it has been reclassified as a quantifier
If 'this exists' is analytic, either the thing is a thought, or you have presupposed its existence
Kant never denied that 'exist' could be a predicate - only that it didn't enlarge concepts
Is "This thing exists" analytic or synthetic?
28. God / D. Proofs of Evidence / 1. Cosmological Proof
If you prove God cosmologically, by a regress in the sequences of causes, you can't abandon causes at the end