Framework · Influence · Influence
Influence: the six principles
Robert Cialdini's Influence (revised edition) groups the tactics he observed into six principles: reciprocation, commitment and consistency, social proof, liking, authority and scarcity. Each is a usually reliable shortcut set off by a few cues, and contrast amplifies all six. Here they govern the decision points: sign-up, permission, upgrade, checkout, renewal, referral.
Plain label: six shortcuts behind most yesesAlso known as: Cialdini, Influence, weapons of influence, principles of persuasion, decision-point lens
Cialdini spent years in the lab and about three years inside sales, fundraising and advertising training programs, then sorted the tactics he saw into six principles (Introduction, pp.v-vii). Each principle is a shortcut that usually points to a good decision, which is why people rely on it and why anyone who knows its cue can borrow it (Ch.1, pp.7-9).
| Principle | The shortcut | Strongest when | Where |
|---|---|---|---|
| Reciprocation | Repay what was given first | The gift or concession comes first, even unasked | Ch.2, pp.13-42 |
| Commitment and consistency | Stay consistent with a prior stand | The stand is active, public, effortful and freely chosen | Ch.3, pp.43-86 |
| Social proof | If others do it, it is probably right | People are uncertain and the others are similar | Ch.4, pp.87-125 |
| Liking | Say yes to people we like | The ask comes through a friend or after a pleasant moment | Ch.5, pp.126-156 |
| Authority | Defer to legitimate expertise | The expert is real and relevant to the question | Ch.6, pp.157-177 |
| Scarcity | Less available seems more valuable | It is newly scarce, and scarce because of demand | Ch.7, pp.178-203 |
Contrast is not a principle of its own but an amplifier: what comes second looks more different from the first than it is (see in-contrast-principle). Click, whirr is the model underneath: one cue sets off a stored response (see in-click-whirr). This is the revised edition, which has six principles.
How the knowledge base uses it [S]. Each decision point gets a coverage score per principle: 0 absent, 1 generic, 2 specific and placed at the moment of uncertainty, 3 all of that plus the right sequence and contrast and an identified deciding cue. Technique entries carry the principle they rely on and the decision points they fit.
Evidence. The principles rest on lab and field studies from the 1960s to the early 1990s and on the author's field observation. Treat book numbers as headline effects from single studies, not forecasts; several are much smaller in later meta-analyses.
Sources
Influence · Robert Cialdini
Intro · Ch.1, p.8
Book content is paraphrased, never quoted at length. Last verified October 24, 2026.
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