Robert Cialdini
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The author went undercover to learn about 'compliance practitioners’ (salesmen, con artists, advertisers and fund-raisers). He distilled the tactics into a handful of “weapons of influence”.

Weapons of influence consist of identifying fixed action patterns and exploiting them. Compliance practitioners use them as a basis for influence.

  1. Reciprocation — We should try to repay in kind, what another person has provided us.
  2. Commitment — We have a nearly obsessive desire to be consistent with what we have already done.
  3. Social Proof — We view a behavior as more correct in a given situation to the degree that we see others performing it.
  4. Liking — What causes liking?
  5. Authority — We obey authorities mindlessly in a lot of cases.
  6. Scarcity — The thought of losing something motivates us more than the thought of gaining something of similar value.

Persuasion vs. Coercion


Communicators try to convince other people to change their own attitudes/behaviours about an issue through transmission of message with free choice

People must change their own attitudes based on arguments or baits from persuasive messages


Freedom of choice is removed

Click-Whirr (heuristic)

An automatic, fixed-action pattern of response that is efficient most of the time. Although trigger features can cause us to activate it at the wrong time.

“Civilization advances by extending the number of operations we can perform without thinking about them.” - Alfred North Whitehead

Contrast Principle

Humans perceive things which are presented one after the other differently than those presented in isolation.

  1. Showing an inexpensive product before an expensive one causes the latter to look even more expensive. Cloth sellers will try to make the buyer buy the most expensive item on their list first.
  2. Real estate companies have setup properties which are expensive or run down properties. They lower customers expectations, so that, later on, when they see an actual house, they like it.
  3. Automobile dealers negotiate a new car’s price first before suggesting add-ons.

1. Reciprocation

Rule of reciprocation: we should try to repay, in kind, what another person has provided us.

There is a general distaste for those who make no effort to reciprocate. We will often go to great lengths to avoid being seen as one of them.

This rule is so overpowering that even if we don’t like someone, we can end up complying with their request.

Each of us has been taught to live up to the rule, and all of us know the social sanctions and derision applied to anyone who violates it.

Reciprocal concessions

General rule of reciprocity: a person who acts in a certain way towards us is entitled to a similar return action

Thus, a consequence of the rule is that an obligation to make a concession to someone who has made a concession to us

It happens because of the benefit: it is in the interest of any human group to have its members work together towards the achievement of common goals

Society must arrange to have these initial, incompatible desires set aside for the sake of socially beneficial cooperation.

We feel more responsible and satisfied after agreeing to a concession. We think we have brought that change.

Rejection-then-retreat technique

Make a larger request of me, one that I will likely turn down

Then, after I have refused, make the smaller request that you were really interested in all-along your 2nd request will be viewed as a concession and I will respond with a concession of my own

However, if the first set of demands are so extreme as to be seen as unreasonable, the tactic fails

It also takes advantage of the contrast principle: the smaller request looks even smaller by comparison with the larger one.

It works because the subject (who the tactic is being used on) feels that they successfully influenced you to do less.

How To Say No

It’s important to identify that we are being pulled into reciprocation for commercial reasons.

The act of mental redefinition, in that case, will tell us to avoid reciprocating when the original action had a commercial intent.

2. Commitment and Consistency

We have a nearly obsessive desire to be consistent with what we have already done.

Why consistency

Valuable and adaptive

Person whose belief, words and deeds don’t match are considered indecisive, confused and two-faced.

A high degree of consistency is normally associated with personal and intellectual strength

Consistency offers a shortcut through life; it allows us a convenient, relatively effortless and efficient method for dealing
with complex daily environments that make severe demands on our mental energies and capacities

The 2nd attraction to consistency is that we can avoid harsh consequences of hard, cognitive work

What produces the automatic tape of consistency?


If I can get you to make a commitment, I have set the stage for your automatic and ill-considered consistency with that earlier commitment

Foot-in-the-door technique

Start with a small request then gain eventual compliance over larger requests.

Small commitments can manipulate a person’s self-image

Commitment conditions

You look at a person’s actions to decide what kind of a person he is

The person himself actually also uses the same evidence to decide what he is like

His behaviour tells him about himself; it is a primary source of information about his beliefs, attitudes and self-perception.


An exploitative individual can offer us an inducement for making the choice, then after the decision has been made, remove that inducement, because he knows that the commitment we have made will stand on its 2 legs.

How To Say No

Ask yourself “Would I make the same choice again?” (had it not been for what I have said or what has been extracted out of me by the compliance practitioner in the near past).

If the answer is no, then don’t debate the reason for saying yes, just say no and move on.

3. Social Proof

One way we use to determine what is correct is to find out what other people think is correct

We view a behaviour as more correct in a given situation to the degree we see others performing it

It works well because as a rule, we make fewer mistakes by acting in accordance with social evidence than contrary to it.

Optimal Condition for Social Proof: Pluralistic Ignorance

In the process of examining the reactions of other people to resolve our uncertainty, we are likely to overlook a subtle but important fact — those ppl are probably examining the social evidence as well

In an ambiguous situation, the tendency for everyone to be looking to see what everyone else is doing is a phenomenon called pluralistic ignorance

Bystander Effect

Failure of entire group of bystanders to aid victims in agonising need of help

Why Bystander Effect occurs:

Diffusion of Responsibility — personal responsibility of each individual is reduced when more and more people are around

Optimal Condition for Social Proof: Similarity

We are more inclined to follow the lead of an individual who is similar to us

How To Say No

Recognise when social proof is deliberately faked (e.g., canned laughter).

Recognise where social proof is a snowball. A snowball is when no one knows anything, and everyone believes that everyone else knows something which they don’t.

In both of these cases, stop following the crowd.

4. Liking

We most prefer to say yes to the requests of someone we know and like.

Compliance professionals just need to get us to like them. How?

Factor 1: Physical Attractiveness

There is a click, whirr response to attractive people

The response falls into a category called Halo Effect

Halo Effect: one positive characteristic of a person dominates the way that person is viewed by others

We automatically assign to good-looking individuals favourable traits such as kindness, talent, honesty and intelligence.

We make these judgments without being aware that physical attractiveness plays a role in the process

Factor 2: Similarity

We like people who are similar to us

We are more likely to help people who dress like us

People can manipulate similarity by claiming that they have backgrounds and interests similar to us.

Factor 3: Compliments

You like people who like you

We are suckers for flattery, even if it is fake

Factor 4: Contact and Cooperation

We like things that are familiar to us

Factor 5: Conditioning and Association

People blame the weathermen when the weather turns bad; people kill the messenger (in ancient times) when they brought bad news

A natural human tendency to dislike a person who brings us unpleasant information, even when that person did not cause the bad news

Compliance professionals try to connect themselves with the things we like in order to try to create positive associations

How To Say No

Keep your feelings for the requestor and the request separate. If you like the requester, do not automatically like the request.

5. Authority

A multilayered and widely accepted system of authority has an advantage: allows the development of sophisticated structures for resource production, trade, defence, expansion and social control that would otherwise be impossible

We are also trained from young to learn that obedience to proper authority is right and disobedience is wrong.

Authority can also be due to religious instruction, for e.g the first book of the Bible describes how failure to obey the ultimate authority produced the loss of paradise for Adam, Eve and the rest of the human race.

Conforming to dictates of authority had early advantages. When we were young, these people (for e.g teachers, parents) knew more than we did and we found that taking their advice proved beneficial.

There are factors that can convey authority, which affects us.

Factor 1: Titles

People can adopt the label without putting in effort and receive a kind of automatic deference.

e.g. Someone being introduced as a professor is seen taller by students than someone being introduced as a graduate student.

Factor 2: Clothes and other outward appearances

Cloak of authority is fakable

e.g. Motorists wait much longer before honking on a new luxury car than an old car. And people, when asked about it, underestimate that effect.

Factor 3: Trappings/Expensive Items

e.g Jewellery, cars

How To Say No

Ask yourself, “is this authority truly an expert?”.

Think what does this expert stand to gain by my compliance.

An expert has a higher chance of swaying us if we think he is impartial.

6. Scarcity

Opportunities seem more valuable to us when their availability is limited

People are also more motivated by the thought of losing something than by the thought of gaining something of equal value

Scarcity Works Because:

1) Familiar: we have a mental shortcut that tells us that things that are difficult to possess are typically better than those
that are easy to possess.

2) as opportunities are less available, we lose freedoms (due to psychological reactance theory)

Psychological Reactance Theory:

Whenever free choice is limited or threatened, the need to retain our freedoms make us desire them significantly more than previously.

Scarcity Applies To Information:

We find a piece of information more persuasive if we think we can’t get it elsewhere

Limited Number Tactic:

Customer is informed that a certain product is in short supply that cannot be guaranteed to last long.

Sometimes limited number is true, sometimes it is false

The intent is always to convince customers of an item’s scarcity and then increase its immediate value in their eyes

Deadline Tactic:

Some official time limit is placed on the customer’s opportunity to get what the compliance professional is offering

Sometimes used in face-to-face selling, customers are often told unless they make an immediate decision to buy, they will have to purchase the item at a higher price or they will be unable to purchase at all.

How To Say No

The real enjoyment is in experiencing something than just possessing it.

The scarcity pushes us into buying things just for the sake of possessing them.

Think about whether you are going after something because it is scarce or because it is useful.