deductive
Americanadjective
adjective
Commonly Confused
Deductive and inductive refer to two distinct logical processes. Deductive reasoning is a logical process in which a conclusion drawn from a set of premises contains no more information than the premises taken collectively. All dogs are animals; this is a dog; therefore, this is an animal: The truth of the conclusion is dependent only on the method. All men are apes; this is a man; therefore, this is an ape: The conclusion is logically true, although the premise is absurd. Inductive reasoning is a logical process in which a conclusion is proposed that contains more information than the observations or experience on which it is based. Every crow ever seen was black; all crows are black: The truth of the conclusion is verifiable only in terms of future experience and certainty is attainable only if all possible instances have been examined. In the example, there is no certainty that a white crow will not be found tomorrow, although past experience would make such an occurrence seem unlikely.
Other Word Forms
- deductively adverb
- nondeductive adjective
- nondeductively adverb
- undeductive adjective
- undeductively adverb
Etymology
Origin of deductive
First recorded in 1640–50, deductive is from the Latin word dēductīvus derivative. See deduct, -ive
Example Sentences
Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
Then again, those New Year’s Eve revelers may have had their powers of basic detection and deductive reasoning sharpened by being led astray by AI slop.
From Salon • Jan. 21, 2026
Not through any kind of intuition or deductive superpower, mind you.
From Los Angeles Times • Jan. 9, 2025
Instead of receiving science through set experiments with known outcomes, students should learn to apply deductive and inductive reasoning to weigh information before blindly accepting results.
From Scientific American • Aug. 16, 2023
The pangram from yesterday’s Spelling Bee was deductive.
From New York Times • May 25, 2023
Moral certainty, grounded in probability, had, in the writings of Wilkins and Locke, joined deductive or self-evident knowledge as a form of truth.
From "The Invention of Science" by David Wootton
Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.
