24 Ludwig Wittgenstein Quotes on Logic

Ludwig Wittgenstein quotes on logic

2. I cannot get from the nature of the proposition to the individual logical operations!!! That is, I cannot bring out how far the proposition is the picture of the situation. I am almost inclined to give up all my efforts. (p. 41)

11. That all elementary props are given is SHOWN by there being none having an elementary sense which is not given.

14. The world is all that is the case. (1)

15. The world is the totality of facts, not things. (1.1)

16. What is the case, the fact, is the existence of atomic facts. (2)

17. The logical picture of the facts is the thought. (3)

19. Philosophy aims at the logical clarification of thoughts. Philosophy is not a body of doctrine but an activity. A philosophical work consists essentially of elucidations. Philosophy does not result in 'philosophical propositions', but rather in the clarification of propositions. Without philosophy thoughts are, as it were, cloudy and indistinct: its task is to make them clear and to give them sharp boundaries. (4.112)

20. It is quite impossible for a proposition to state that it itself is true. (4.442)

21. A tautology's truth is certain, a proposition's possible, a contradiction's impossible. (Certain, possible, impossible: here we have the first indication of the scale that we need in the theory of probability.) (4.464)

22. Propositions are truth-functions of elementary propositions. (An elementary proposition is a truth-function of itself.) (5)

23. If I cannot say a priori what elementary propositions there are, then the attempt to do so must lead to obvious nonsense. (5.5571)

25. Logic pervades the world: the limits of the world are also its limits. So we cannot say in logic, 'The world has this in it, and this, but not that.' For that would appear to presuppose that we were excluding certain possibilities, and this cannot be the case, since it would require that logic should go beyond the limits of the world; for only in that way could it view those limits from the other side as well. We cannot think what we cannot think; so what we cannot think we cannot say either. (5.61)

35. A proposition is completely logically analyzed if its grammar is made clear in no matter what idiom. Part I(1)

38. What should we gain by a definition, as it can only lead us to other undefined terms? (p. 26)

60. 1. If you do know that here is one hand, we'll grant you all the rest.

61. 94. But I did not get my picture of the world by satisfying myself of its correctness; nor do I have it because I am satisfied of its correctness. No: it is the inherited background against which I distinguish between true and false.

63. 205. If the true is what is grounded, then the ground is not true, nor yet false.

65. 225. What I hold fast to is not one proposition but a nest of propositions.

76. If you use a trick in logic, whom can you be tricking other than yourself? (p. 24e)

101. I am sitting with a philosopher in the garden; he says again and again 'I know that that's a tree', pointing to a tree that is near us. Someone else arrives and hears this, and I tell them: 'This fellow isn't insane. We are only doing philosophy.' (p. 578)

115. If there were a verb meaning 'to believe falsely,' it would not have any significant first person, present indicative.

117. In order to be able to set a limit to thought, we should have to find both sides of the limit thinkable (i.e. we should have to be able to think what cannot be thought). (preface, Tractatus Logico-Philosophicus)

123. Logic takes care of itself; all we have to do is to look and see how it does it.

131. The logic of the world is prior to all truth and falsehood.