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
Wittgenstein's picture theory is the best version of the correspondence theory of 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
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 sign of identity is not allowed in 'Tractatus'
The identity sign is not essential in logical notation, if every sign has a different meaning
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
The concept of number is just what all numbers have in common
A number is a repeated operation
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 as Non-Physical / 2. A Priori Self
The subject stands outside our understanding of the world
19. Language / A. Language / 1. Language
The limits of my language means the limits of my world
What can be said is what can be thought, so language shows the limits of thought
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