From Paul Waring
As an avid fan and one who uses the stories of Sherlock Holmes to demonstrate inference, I really enjoyed your book reviews on the great detective and his science (5 January, p 40). In them you mention his use of deductive reasoning, which in its strictest definition means that based on the assumption of true reasons the answer is guaranteed true.
However, author Arthur Conan Doyle probably assumed the more common meaning of “deduction” as a process leading to a conclusion so that an audience not necessarily skilled in either science or logic could understand.
Holmes of course uses that form of reasoning which gave 18th century philosopher David Hume so many problems and which produces new knowledge with a high probability of truth – inductive reasoning.
Canberra, ACT, Australia
