The Science of Deduction: How Sherlock Holmes Actually Thinks

‘You see, but you do not observe.’ It is the essence of Sherlock Holmes, and the reason he has never gone out of print since he first appeared. But how does the famous method actually work — and is it really ‘deduction’ at all?

Strictly, no. What Holmes does is closer to what logicians call abduction — inference to the best explanation. He notices a hundred tiny details everyone else ignores (the callus on a thumb, the mud particular to one district, the wear on a sleeve), and reasons backward to the single story that would explain them all. It looks like magic because the rest of us never gathered the data; Holmes’s genius is less in the reasoning than in the seeing, the relentless attention that treats nothing as too small to matter.

Conan Doyle modelled him on a real Edinburgh surgeon, Dr Joseph Bell, who could diagnose a patient’s trade and history from a glance — and in doing so Doyle helped invent the very idea of forensic science, of solving crime by evidence and inference rather than confession and luck. Real detectives learned from the fictional one.

This edition gathers the complete Sherlock Holmes — every case, from the first spark to the last bow.

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