Deduction, Induction, and Analogy
What is Deduction, Induction, and Analogy?
Three basic ways of reasoning. Deduction moves from a general rule to a specific conclusion, and when the premises are true and the form valid the conclusion follows necessarily — “contracts over $100k need legal review; this one is $150k; so it needs review” — provided the rule is real and applies to this case. Induction generalises from specific instances, and the conclusion is only probable — “regions that respond faster have higher renewal rates” — with reliability depending on sample size, representativeness, counterexamples, and other variables in play. Analogy infers from a resemblance in some respects that other respects match too — “the online channel worked for our competitor, so it may work for us”; “family meetings cut the arguing at my friend’s house, so they may at ours”. An analogy can open a line of thought but cannot carry a proof by itself: always ask whether the resemblance is relevant to the conclusion, and whether the differences are large enough to change the outcome.
Deduction, Induction, and Analogy: common mistakes and how to handle them
Mature reasoning means knowing which method fits the situation and how much weight the conclusion can bear. A single job application uses all three: deriving the skills a role needs from its stated duties is deduction, reading a growth opportunity out of market data is induction, and comparing the skills of a coroner with those of a manager is analogy.
What the Deduction, Induction, and Analogy questions test
identifying which of the three a passage uses; judging whether a conclusion is necessary or merely probable; naming where each type’s premises could fail; spotting an analogy treated as proof, or an induction treated as certainty.