The propositions of logic demonstrate the logical properties of propositions in that they combine them to form propositions without content. This could also be called a null method. In a logical proposition, propositions are brought into equilibrium with one another, and that equilibrium then indicates what the logical constitution of these propositions must be.
It follows from this that we can even do without logical propositions because a suitable notation enables one to recognize the formal properties of propositions by inspection. If, for example, two propositions (p) and (q) in the compound proposition (p⊃q) yield a tautology, then it is clear that (q) follows from (p). That (q) follows from (p⊃q.p) is seen from the two propositions themselves, but it is also possible to show it by combining them to form (p⊃q.p:⊃:q), and then showing that this is a tautology.
Logical propositions cannot be confirmed by experience any more than they can be refuted by it. Not only must a proposition of logic be irrefutable by any possible experience, but it must also be unconfirmable by any possible experience. We can postulate the truths of logic in sthat we can postulate an adequate notation. Clearly: the laws of logic cannot themselves be subject to laws of logic. (There is not, as Russell thought, a special law of contradiction for each 'type'; one law is enough instead, since it is not applied to itself.)
The mark of a logical proposition is not general validity, since that only means to be valid for all things by happenstance. An ungeneralized proposition can just as well be tautological as a generalized one.
We could call logical generality essential, in contrast with the accidental generality of such propositions as 'All men are mortal'. Propositions like Russell's 'axiom of reducibility' are not logical propositions, and this explains our feeling that, even if they were true, their truth could only be the result of a fortunate accident.
One can imagine a world in which the axiom of reducibility is not valid. But it is clear that logic has nothing to do with the question of whether our world is really so or not.
Logical propositions describe the structural skeleton of the world. They have no content on their own, but presuppose that names have meaning and elementary propositions make sense; and that connects them to the world. Clearly, it must show something about the world that certain conjunctions of symbols—that in essence have a specific character—are tautologies. This is a decisive point.
Some things are arbitrary in the symbols that we use and some things are not. In logic, only the latter express. That does not mean we express what we wish with the help of signs, but rather that one in which the nature of the absolutely necessary signs speaks for itself. If we know the logical syntax of any symbolic language, then we have already been given all the propositions of logic.
This log was inspired by "How to Read Wittgenstein" and "Ludwig Wittgenstein: the duty of genius" by Ray Monk. It is based on reading Tractatus LogicoPhilosophicus by Ludwig Wittgenstein translated by D. F. Pears & B. F. McGuinness (Routledge and Kegan Paul:1963)
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 Tractatus LogicoPhilosophicus 1
 Tractatus LogicoPhilosophicus 2
 Tractatus LogicoPhilosophicus 2.01
 Tractatus LogicoPhilosophicus 2.02
 Tractatus LogicoPhilosophicus 2.03 to 2.063
 Tractatus LogicoPhilosophicus 2.1
 Tractatus LogicoPhilosophicus 2.2
 Tractatus LogicoPhilosophicus 3
 Tractatus LogicoPhilosophicus 3.0
 Tractatus LogicoPhilosophicus 3.1
 Tractatus LogicoPhilosophicus 3.2
 Tractatus LogicoPhilosophicus 3.3
 Tractatus LogicoPhilosophicus 3.32
 Tractatus LogicoPhilosophicus 3.33
 Tractatus LogicoPhilosophicus 3.34
 Tractatus LogicoPhilosophicus 3.4 to 3.5
 Tractatus LogicoPhilosophicus 4
 Tractatus LogicoPhilosophicus 4.00
 Tractatus LogicoPhilosophicus 4.01 to 4.022
 Tractatus LogicoPhilosophicus 4.023 to 4.027
 Tractatus LogicoPhilosophicus 4.03
 Tractatus LogicoPhilosophicus 4.04
 Tractatus LogicoPhilosophicus 4.05 to 4.0621
 Tractatus LogicoPhilosophicus 4.1
 Tractatus LogicoPhilosophicus 4.12 to 4.1213
 Tractatus LogicoPhilosophicus 4.122 to 4.1252
 Tractatus LogicoPhilosophicus 4.126 to 4.128
 Tractatus LogicoPhilosophicus 4.2 to 4.28
 Tractatus LogicoPhilosophicus 4.3 to 4.442
 Tractatus LogicoPhilosophicus 4.45 TO 4.4661
 Tractatus LogicoPhilosophicus 4.5 to 4.53
 Tractatus LogicoPhilosophicus 5
 Tractatus LogicoPhilosophicus 5 to 5.101
 Tractatus LogicoPhilosophicus 5.05 to 5.156
 Tractatus LogicoPhilosophicus 5.11 to 5.132
 Tractatus LogicoPhilosophicus 5.133 to 5.143
 Tractatus LogicoPhilosophicus 5.2 to 5.254
 Tractatus LogicoPhilosophicus 5.3
 Tractatus LogicoPhilosophicus 5.4 to 5.44
 Tractatus LogicoPhilosophicus 5.45
 Tractatus LogicoPhilosophicus 5.46 to 5.472
 Tractatus LogicoPhilosophicus 5.473 to5.476
 Tractatus LogicoPhilosophicus 5.5 to 5.503
 Tractatus LogicoPhilosophicus 5.51
 Tractatus LogicoPhilosophicus 5.52
 Tractatus LogicoPhilosophicus 5.53 to 5.535
 Tractatus LogicoPhilosophicus 5.5351 to 5.5352
 Tractatus LogicoPhilosophicus 5.55 to 5.5571
 Tractatus LogicoPhilosophicus 5.6 to 5.621
 Tractatus LogicoPhilosophicus 5.63 to 5.641
 Tractatus LogicoPhilosophicus 6
 Tractatus LogicoPhilosophicus 6 to 6.01
 Tractatus LogicoPhilosophicus 6.1 to 6.1202
 Tractatus LogicoPhilosophicus 6.1203
 Tractatus LogicoPhilosophicus 6.121 to 6.124
 Tractatus LogicoPhilosophicus 6.125 to 6.1271
 Tractatus LogicoPhilosophicus 6.13 to 6.2331
 Tractatus LogicoPhilosophicus 6.234 to 6.3432
 Tractatus LogicoPhilosophicus 6.342 to 6.372
 Tractatus LogicoPhilosophicus 6.373 to 6.3751
 Tractatus LogicoPhilosophicus 6.5
 Tractatus LogicoPhilosophicus 7
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 The world does not depend on me.
 The relative position of logic and science.
 Mathematics is a method of logic.
 Logic is transcendental.
 One can describe all true logical propositions in ...
 We can do without logical propositions.
 Recognizing a Tautology.
 The propositions of logic are tautologies.
 The General Form of a Truth Function.
 The microcosm.
 The boundary of my language represents the boundar...
 Elemental Propositions.
 Propositions occur in each other only as bases of ...
 Expressions.
 Identity.
 Truth Functions do not Include the Concept All.
 How is this useful?
 Every truthfunction an be obtained by successivel...
 Occam's rule points out that unnecessary signs mea...
 Signs for logical operations are punctuation marks...
 Logic must be clearly constructed from its primiti...
 Logical objects or logical constants in Frege's an...
 All propositions are the result of truth operators...
 The structures of propositions relate internally t...
 Propositions of probability.
 All deduction is a priori.
 Logical Inference.
 A proposition is a truth function of elemental pro...
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 Tautology and Contradiction.
 Truth Value Tables and Propositions.
 The sense of a proposition.
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 Formal Properties and Relations.
 Logical Form  What can be shown, cannot be said.
 A proposition exhibits matters of fact which both ...
 Every proposition must make sense on its own.
 A proposition can be true or false only by being a...
 A proposition must have just as many degrees of fr...
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