Ideas from 'Tractatus Logico-Philosophicus' by Ludwig Wittgenstein [1921], by Theme Structure

[found in 'Tractatus Logico-Philosophicus' by Wittgenstein,Ludwig (ed/tr Pears,D. /McGuinness,B.) [RKP 1961,0-7100-7923-0]].

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1. Philosophy / D. Nature of Philosophy / 1. Philosophy
What we cannot speak about we must pass over in silence
1. Philosophy / D. Nature of Philosophy / 3. Philosophy Defined
I say (contrary to Wittgenstein) that philosophy expresses what we thought we must be silent about
1. Philosophy / D. Nature of Philosophy / 5. Hopes for Philosophy
If a question can be framed at all, it is also possible to answer it
1. Philosophy / D. Nature of Philosophy / 6. Despair over Philosophy
The 'Tractatus' is a masterpiece of anti-philosophy
1. Philosophy / F. Analytic Philosophy / 1. Analysis
All complex statements can be resolved into constituents and descriptions
2. Reason / B. Laws of Thought / 6. Ockham's Razor
If a sign is useless it is meaningless; that is the point of Ockham's maxim
3. Truth / B. Truthmakers / 2. Truthmaker Relation
The best account of truth-making is isomorphism
3. Truth / B. Truthmakers / 11. Truthmaking and Correspondence
All truths have truth-makers, but only atomic truths correspond to them
3. Truth / C. Correspondence Truth / 1. Correspondence Truth
Language is [propositions-elementary propositions-names]; reality is [facts-states of affairs-objects]
Pictures reach out to or feel reality, touching at the edges, correlating in its parts
Wittgenstein's picture theory is the best version of the correspondence theory of truth
5. Theory of Logic / A. Overview of Logic / 3. Value of Logic
Wittgenstein is right that logic is just tautologies
5. Theory of Logic / A. Overview of Logic / 4. Pure Logic
Logic is a priori because it is impossible to think illogically
5. Theory of Logic / B. Logical Consequence / 3. Deductive Consequence |-
If q implies p, that is justified by q and p, not by some 'laws' of inference
5. Theory of Logic / C. Ontology of Logic / 1. Ontology of Logic
The propositions of logic are analytic tautologies
5. Theory of Logic / C. Ontology of Logic / 2. Platonism in Logic
Wittgenstein convinced Russell that logic is tautologies, not Platonic forms
5. Theory of Logic / D. Assumptions for Logic / 4. Identity in Logic
The identity sign is not essential in logical notation, if every sign has a different meaning
The sign of identity is not allowed in 'Tractatus'
5. Theory of Logic / E. Structures of Logic / 1. Logical Form
Apparent logical form may not be real logical form
5. Theory of Logic / E. Structures of Logic / 2. Logical Connectives / a. Logical connectives
My fundamental idea is that the 'logical constants' do not represent
5. Theory of Logic / E. Structures of Logic / 4. Variables in Logic
'Object' is a pseudo-concept, properly indicated in logic by the variable x
5. Theory of Logic / F. Referring in Logic / 1. Naming / c. Names as referential
A name is primitive, and its meaning is the object
5. Theory of Logic / H. Proof Systems / 1. Proof Systems
Logical proof just explicates complicated tautologies
5. Theory of Logic / I. Semantics of Logic / 3. Logical Truth
Logical truths are just 'by-products' of the introduction rules for logical constants
5. Theory of Logic / K. Features of Logics / 1. Axiomatisation
Logic doesn't split into primitive and derived propositions; they all have the same status
6. Mathematics / B. Foundations for Mathematics / 4. Definitions of Number / a. Defining numbers
A number is a repeated operation
The concept of number is just what all numbers have in common
6. Mathematics / B. Foundations for Mathematics / 5. Mathematics as Set Theory / b. Mathematics is not set theory
The theory of classes is superfluous in mathematics
6. Mathematics / C. Sources of Mathematics / 6. Logicism / d. Logicism critique
Wittgenstein hated logicism, and described is as a cancerous growth
7. Existence / A. Nature of Existence / 1. Nature of Existence
The world is facts, not things. Facts determine the world, and the world divides into facts
7. Existence / C. Structure of Existence / 6. Fundamentals / d. Logical atoms
The 'Tractatus' is an extreme example of 'Logical Atomism'
8. Modes of Existence / A. Relations / 2. Internal Relations
The order of numbers is an internal relation, not an external one
A relation is internal if it is unthinkable that its object should not possess it
9. Objects / F. Identity among Objects / 1. Concept of Identity
Identity is not a relation between objects
9. Objects / F. Identity among Objects / 5. Self-Identity
Two things can't be identical, and self-identity is an empty concept
9. Objects / F. Identity among Objects / 7. Indiscernible Objects
It at least makes sense to say two objects have all their properties in common
10. Modality / A. Necessity / 3. Types of Necessity
The only necessity is logical necessity
10. Modality / E. Possible worlds / 3. Transworld Objects / a. Transworld identity
To know an object you must know all its possible occurrences
10. Modality / E. Possible worlds / 3. Transworld Objects / d. Haecceitism
Two objects may only differ in being different
12. Knowledge Sources / A. A Priori Knowledge / 2. Self-Evidence
If the truth doesn't follow from self-evidence, then self-evidence cannot justify a truth
12. Knowledge Sources / A. A Priori Knowledge / 8. A Priori as Analytic
Logic and maths can't say anything about the world, since, as tautologies, they are consistent with all realities
12. Knowledge Sources / A. A Priori Knowledge / 10. A Priori as Subjective
Logic is a priori because we cannot think illogically
12. Knowledge Sources / D. Empiricism / 1. Empiricism
Good philosophy asserts science, and demonstrates the meaninglessness of metaphysics
13. Knowledge Criteria / D. Scepticism / 1. Scepticism
Doubts can't exist if they are inexpressible or unanswerable
14. Science / B. Scientific Theories / 3. Instrumentalism
The 'Tractatus' is instrumentalist about laws of nature
14. Science / C. Induction / 2. Aims of Induction
Induction accepts the simplest law that fits our experiences
14. Science / D. Explanation / 2. Types of Explanation / d. Lawlike explanations
The modern worldview is based on the illusion that laws explain nature
16. Persons / D. Self and Body / 2. A Priori Self
The subject stands outside our understanding of the world
19. Language / A. Language / 1. Language
What can be said is what can be thought, so language shows the limits of thought
The limits of my language means the limits of my world
19. Language / B. Meaning / 3. Meaning as Verification
Good philosophy should show that metaphysical remarks use meaningless signs
19. Language / B. Meaning / 6. Meaning as Truth-Conditions
To understand a proposition means to know what is the case if it is true
22. Metaethics / B. Basis of Ethics / 1. Morality
Ethics cannot be put into words
22. Metaethics / B. Basis of Ethics / 4. Is/Ought
The sense of the world must lie outside the world