It was probably on 4 March 1881 when Dr Watson's attention was caught by a peculiar piece of writing entitled "The Book of Life". After perusing it, he pronounced it to be "ineffable twaddle". The article turned out to be written by Sherlock Holmes himself and gave an outline of his methods in a strange mixture of rationalist argument and philosophical camouflage. "From a drop of water", said the writer, "a logician could infer the possibility of an Atlantic or a Niagara without having seen or heard of one or the other. So all life is a great chain, the nature of which is unknown whenever we are shown a single link of it" (Doyle 29). The Platonic overtones — particularly in view of the initiation to be undergone by the candidate in the Science of Deduction and Analysis — not only give the lie to Holmes's alleged philosophical and literary deficits listed by Watson in A Study in Scarlet (1887) but are also elements in the ideological forces that shaped the genre of the detective story.