Framework · Influence · Influence
Authority
People defer to legitimate authority, often reacting to its symbols (titles, clothes, trappings) as strongly as to substance, and they underestimate how much it moves them. Credibility combines expertise and trustworthiness, and arguing against one's own interest is one of the strongest trust signals.
Plain label: deference to legitimate expertiseAlso known as: authority, expertise, credibility, titles, trust signals
The model INF-M-56 (Influence Ch.6, p.157) (Ch.6, pp.157-165). Obedience to authority is taught early and is usually useful, so it runs automatically, even when it should not.
Three symbols INF-M-57 (Influence Ch.6, p.165) (Ch.6, pp.165-172): titles (hardest to earn, easiest to fake), clothes and trappings. People predicted far less deference to a uniform than they actually showed.
Two questions INF-M-58 (Influence Ch.6, p.172) (Ch.6, pp.172-174). Is this a real expert on this particular topic? Can they be trusted here, given what they stand to gain? See in-t-au-01 and in-t-au-05.
Trustworthiness. Admitting a small weakness, or pointing to a cheaper option, makes the main claims more believable (Ch.6, pp.174-176), see in-t-au-07 and in-t-au-08. Contradictory authorities stop people altogether (Ch.6, pp.161-162), see in-t-au-13.
Evidence. The obedience studies have been only partly replicated, and the nurse result fell sharply when nurses were familiar with the drug and able to check with colleagues. Use the principle to design credibility, not to predict obedience.
Sources
Influence · Robert Cialdini
Ch.6, p.157 · Ch.6, p.165 · Ch.6, p.172
Source IDs: INF-M-56INF-M-57INF-M-58
Book content is paraphrased, never quoted at length. Last verified October 24, 2026.
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