6.36111 (2/3) [IMAGE-636111] in which the two congruent figures, a and b, cannot be made to coincide unless they are moved out of this space. The right hand and the left hand are in fact completely congruent. It is quite irrelevant that they cannot be made to coincide.

6.241 Thus the proof of the proposition 2×2=4 runs as follows: [IMAGE-6241]

6.1203 (4/5) In our notation the form ‘~ξ’ is written as [IMAGE-61203-c] and the form ‘ξ.η’ as [IMAGE-61203-d] Hence the proposition ~(p.~q) reads as follows [IMAGE-61203-e] If we here substitute ‘p’ for ‘q’ and examine how the outermost T and F are connected with the innermost ones,

6.1203 (2/5) [IMAGE-61203-a] and I use lines to express the correlation of the truth or falsity of the whole proposition with the truth-combinations of its truth-arguments, in the following way [IMAGE-61203-b] So this sign, for instance, would represent the proposition p⊃q.

6.02 (2/3) I give the following definitions [IMAGE-602] So, in accordance with these rules, which deal with signs, we write the series x, Ω’x, Ω’Ω’x, Ω’Ω’Ω’x,… in the following way Ω0’x, Ω0+1’x, Ω0+1+1’x, Ω0+1+1+1’x,… Therefore, instead of ‘[x, ξ, Ω’ξ]’, I write ‘[Ω0’x, Ων’x,

5.6331 For the form of the visual field is surely not like this Eye —[IMAGE-56331]

5.5423 (2/2) This no doubt also explains why there are two possible ways of seeing the figure [IMAGE-55423] (If I look in the first place at the corners marked a and only glance at the b’s, then the a’s appear to be in front, and _vice versa_).

5.101 (2/2) [IMAGE-5101] I will give the name _truth-grounds_ of a proposition to those truth-possibilities of its truth-arguments that make it true.

4.442 (1/4) For example, the following is a propositional sign: [IMAGE-4442] (Frege’s ‘judgement stroke’ ‘⊢’ is logically quite meaningless: in the works of Frege (and Russell) it simply indicates that these authors hold the propositions marked with this sign to be true.

4.42 For n elementary propositions there are [sum from kappa = 0 to Kn of (Kn choose kappa) = Ln][IMAGE-442] ways in which a proposition can agree and disagree with their truth possibilities.

4.31 We can represent truth-possibilities by schemata of the following kind (‘T’ means ‘true’, ‘F’ means ‘false’; the rows of ‘T’s’ and ‘F’s’ under the row of elementary propositions symbolize their truth-possibilities in a way that can easily be understood): [IMAGE-431] pqTTFTTFFFpTF

4.27 For n states of affairs, there are [Kn = sum from nu = 0 to n of (n choose nu)] [IMAGE-427] possibilities of existence and non-existence. Of these states of affairs any combination can exist and the remainder not exist.