Composition Fallacy
LSAT glossary · Logical Reasoning
Definition
A reasoning flaw that infers a property of the whole from a property of its parts — assuming that what is true of each member of a group must be true of the group as a whole. Classic LSAT example: "Every player on the basketball team is outstanding individually; therefore, the team will outperform every other team." The fallacy ignores that collective performance depends on interactions (chemistry, coaching, system fit, teamwork) that do not reduce to individual qualities — five elite players who cannot cooperate may lose to five good players who work together seamlessly.
Composition Fallacy in plain English
The composition fallacy is assuming that because each individual piece has some quality, the whole thing built from those pieces must have it too. The classic trap: "every player on this basketball team is an amazing individual talent, so the team will beat everyone." But a team's success depends on how the players work TOGETHER — chemistry, coaching, sharing the ball — which isn't just the sum of five talents. Five brilliant soloists who never rehearsed together can lose to five decent players who move as one unit, because the whole has properties the parts alone don't guarantee.
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Practice Composition Fallacy
The reasoning in which one of the following arguments is most similar to the flawed reasoning above?
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