Day 83 of 150 Logic Difficulty 3/10

Functional fixedness hides the box as a candle holder

Quick answer

Functional fixedness hides the box as a candle holder. Today's question (Functional fixedness) asks about a finding from Duncker, K. in 1945. The correct option is They fail to see that the box itself can serve as a candle holder (functional fixedness) — full explanation, primary source, and glossary cross-links below.

Today's question

In Duncker's classic candle problem, participants must mount a candle on a wall using a box of tacks, the candle, and matches. Why do most people fail?

  1. A The materials are insufficient for any solution
  2. B They fail to see that the box itself can serve as a candle holder (functional fixedness)
  3. C The candle is too short to use
  4. D They forget which materials are available
Reveal the answer and explanation

Correct: B — They fail to see that the box itself can serve as a candle holder (functional fixedness)

Duncker (1945) showed that participants typically fail the candle problem because they perceive the matchbox as a container — a vessel for tacks — rather than as a structural component that can be tacked to the wall to support the candle. This blind spot, functional fixedness, is the difficulty of using a familiar object outside its conventional role. When the box is presented separately from the tacks, solution rates rise sharply. The candle problem became a foundational tool for studying insight, creativity, and the constraints that prior knowledge places on novel problem solving.

About the source

Duncker, K. (1945). On problem-solving. Psychological Monographs, 58(5), i–113.

Every Cognition Bible question cites a primary source — a paper, book chapter, or monograph that exists, that we can point to on Google Scholar, and whose finding the question accurately summarizes. No fabricated authority strings, no name-drops without paper-level grounding.

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