Simple Definition of deduce
: to use logic or reason to form (a conclusion or opinion about something) : to decide (something) after thinking about the known facts
Examples of deduce
<I can deduce from the simple observation of your behavior that you're trying to hide something from me.>
Origin of deduce
Middle English, from Latin deducere, literally, to lead away, from de- + ducere to lead — more at tow
First Known Use: 15th century
Synonym Discussion of deduce
Sir Thomas More is the first writer known to have used both infer and imply in their approved senses (1528). He is also the first to have used infer in a sense close in meaning to imply (1533). Both of these uses of infer coexisted without comment until some time around the end of World War I. Since then, senses 3 and 4 of infer have been frequently condemned as an undesirable blurring of a useful distinction. The actual blurring has been done by the commentators. Sense 3, descended from More's use of 1533, does not occur with a personal subject. When objections arose, they were to a use with a personal subject (now sense 4). Since dictionaries did not recognize this use specifically, the objectors assumed that sense 3 was the one they found illogical, even though it had been in respectable use for four centuries. The actual usage condemned was a spoken one never used in logical discourse. At present sense 4 is found in print chiefly in letters to the editor and other informal prose, not in serious intellectual writing. The controversy over sense 4 has apparently reduced the frequency of use of sense 3.
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