1. ‘The Greek Interpreter’, in Sir Arthur Conan Doyle, The Memoirs of Sherlock Holmes (London: George Newnes, 1894), p.183.
2. John Dewey, The Quest for Certainty: A Study of the Relation of Knowledge and Action (New York: Capricorn, 1960).
3. It might sometimes be more intuitive to think of the strength of inductive arguments in terms of conditional reasons instead of conditional probability. Contrast Keith Lehrer, Knowledge (Oxford: Clarendon Press, 1974), which analysed justification in terms of probability, with Keith Lehrer, Theory of Knowledge (Routledge, 1990), which analysed justification in terms of reasons. This philosophical distinction will not affect my main points in the text.
4. Assume there are 50,000 cars and 1,000 Fiats in Edinburgh. The witness would identify 90 per cent or 900 of these 1,000 Fiats as Fiats. But he would also misidentify 10 per cent or 4,900 of the 49,000 non-Fiats as Fiats. Thus, out of the 900+4,900=5,800 cars that he would identify as Fiats, only 900/5,800=15.5 per cent really are Fiats.
5. For more on these and other kinds of inductive arguments, see my and Robert Fogelin’s textbook, Understanding Arguments: An Introduction to Informal Logic, 9th edn (Stamford, CT: Cengage Advantage Books, 2014), and my and Ram Neta’s MOOC, ‘Think Again: How to Reason and Argue’, available on the Coursera website.
6. Martin Luther King, Jr., ‘I Have a Dream …’ speech (1963), at < https://www.archives.gov/files/press/exhibits/dream-speech.pdf>
7. General Colin Powell, Address to the United Nations Security Council, 5 February 2003, at <http://www.americanrhetoric.com/speeches/wariniraq/colinpowellunsecuritycouncil.htm>