Thus, propositions of logic (analytic propositions) tell one nothing. So theories that let a logical statement appear to have content are always invalid. One might think, for example, that the words 'true' and 'false' signified properties just like others. Remarkably, every proposition has one of these two properties. Now that seems nothing less than obvious, just as, for instance, the proposition, 'All roses are either yellow or red', would sound obvious if it were true. Indeed, the latter acquires all the characteristics of a proposition of natural science  a sure indication that it has been misconstrued. A valid explanation of the propositions of logic must assign them a unique status among all propositions.
It is the unique characteristic of logical propositions that one can recognize that they are true from the symbol alone. In itself, this fact contains the whole philosophy of logic. And so it is also one of the most important facts that the truth or falsity of nonlogical propositions can not be recognized from the statement alone.
That the propositions of logic are tautologies, is shown by the formal, logical properties of language, of the world. That the constituents of logic, thus connected, yield a tautology, characterizes the logic of those constituents. Propositions must have certain structural properties to yield a tautology when joined in an appropriate way. When they do yield a tautology, that shows they possess these structural properties.
That, for example, the propositions (p) and (~p) yield a tautology in the combination (~(p . ~p)) shows that they contradict one another. The fact that the propositions (p⊃q), (p), and (q), combined with one another in the form ((p⊃q).(p):⊃:(q)), yield a tautology shows that q follows from p and (p⊃q). That ((x).fx:⊃:fa) is a tautology shows that (fa) follows from ((x).fx) etc.
It is clear that one would reach the same conclusions using contradictions instead of tautologies.
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?
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 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.
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 Tautology and Contradiction.
 Truth Value Tables and Propositions.
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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.
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