A. MS. notebook
Published, in part, as 1.521-544 (pp. 68-126, with only the first and last paragraphs deleted). Pages A1-A8, unpublished, are mainly a reply to a listener's note asking, "What makes a Reasoning to be sound?" The note itself (dated November 27, 1903) has been inserted opposite p. A1. Also unpublished is material on the beta part of existential graphs.
Graphs existential, Logic (modal see Modality), Lowell Lectures, Reasoning (probable see also Probability)
pp. 68-126 A1-A8