Carroll diagram Carroll diagram A Carroll diagram, Lewis Carroll's square, biliteral diagram or a "two-way table" is a diagram used for grouping things in a yes/no fashion. Numbers or objects are either categorised as 'x' (having an attribute x) or 'not x' (not having an attribute 'x'). They are named after Lewis Carroll, the pseudonym of Charles Lutwidge Dodgson. Although Carroll diagrams can be as simple as the first one above, the most well known types are those similar to the second one, where two attributes are shown. The <nowiki>'</nowiki>universe<nowiki>'</nowiki> of a Carroll diagram is contained within the boxes in the diagram,
Campbell Dodgson the War Office; his 1918 CBE was a recognition of this work (DNB, 1941-50 : 216). He was the editor, in the 1920s, of "The Print Collector’s Quarterly". He was also a contributor to the "Burlington Magazine" and to the Dictionary of National Biography. Dodgson married Frances Catherine Spooner, daughter of William Archibald Spooner (Warden of New College and the eponymous author of 'Spoonerisms'), in 1913 (DNB, 1941-50 : 216). Dodgson gave generously to the British Museum during his Keepership, but at the same time amassed a very large collection of over 5,000 prints which he bequeathed to the Museum.