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States that the reasoning Dodgson has sent to him is invalid in the last two steps, and explains his conclusions through logical equations. Adds that if Dodgson has 'ingeniously concealed some pitfall into which [Sidgwick has] artlessly fallen', he must bear in mind that [Sidgwick] is professionally a moral philosopher, and not a logician.

Commonplace book of twenty poems by Tennyson, Shelley, Clough, and others, accompanied by a Latin version of Lewis Carroll's "Jabberwocky," titled "Mors Jabrochii" with a note at the bottom that it is a translation "by the late Mr A. A. Vansittart."

Refers to the fallacy involved in the regarding of proposition if A then not C as the contradictory of the proposition if A then C. Refers to the second edition of his Formal Logic, and to a third edition of the latter, which he is working on. Refers to an accompanying slip [not included]. Sets out an argument, involving an equation including Q, R, X, Y and K, and claiming that it is not valid. Concludes that if X is Y, then and are not both true, but that one cannot infer absolutely that and are not both true.

Sketch showing two hedgehogs, representing Rose Macaulay and Margerie Venables Taylor, and a flamingo, representing Miss Lees.

12 Earls Terrace, Kensington, W.8. - In the letter dated 7 October, she writes that it was a pleasure to see him last week, hopes to see him again. In the letter of 28 November, she is sorry he has been ill, invites him for sherry before he goes, has a new [Lewis] Carroll edition from the publishers he may [enjoy on the journey out?]. Accompanied by an envelope addressed to him at 18 Earls Terrace with PS's note at top 'Letter from Miss Ethel Hatch aged 103'.

Requests Sidgwick to give his opinion on a philosophical argument [included].

Sends Sidgwick 'a fuller version' of a paper sent to him on 8 March [not included: see 93/108], and asks him to give his opinion as to the soundness of the reasoning.

Thanks Sidgwick for 'a full and clear reply' [ADD.MS.c/100/93], and claims that the latter's views 'exactly coincide' with his, in relation to the 'argument' in question. Asks Sidgwick who is the chief logician in his university. Recommends 'Magic Pens' to him.