Influence: The Psychology of Persuasion Book Review

You and I exist in an extraordinarily complicated stimulus environment, easily the most rapidly moving and complex that has ever existed on this planet. To deal with it, we need shortcuts. We can’t be expected to recognize and analyze all the aspects in each person, event, and situation we encounter in even on day. We haven’t the time, energy, or capacity for it. Instead, we must very often use our stereotypes, our rules of thumb to classify things according to a few key features and then to respond mindlessly when on or another of these trigger features is present.”

Dr. Cialdini’s book, “Influence: The Psychology of Persuasion” explains the psychology of why people mindlessly say yes, including 6 universal principles and how to use them to become a skilled persuader. This is a *must read* book for business/marketing professionals who want to understand the science of persuasion and the psychological foundations of marketing.

What follows are some of the insights (straight from the book) that I found most fascinating for each principle of influence.


  • By virtue of the reciprocity rule, then, we are obligated to the future repayment of favors, gifts, invitations, and the like.
  • Most of us find it highly disagreeable to be in a state of obligation.
  • Because the rule for reciprocation governs the compromise process, it is possible to use an initial concession as part of a highly effective compliance technique. The technique is a simple one that we can call the rejection-then-retreat technique. Suppose you want me to agree to a certain request. One way to increase your chances would be first to make a larger request of me, one that I will more likely turn down. Then, after I have refused, you would make the smaller request that you were really interested in all along. Provided that you have structured your requests skillfully, I should view your second request as a concession to me and should feel inclined to respond with a concession of my own, the only one I would have immediately open to me — compliance with your second request.
  • If I want you to lend me five dollars, I can make it seem like a smaller request by first asking you to lend me ten dollars and then retreating to five dollars, I will have simultaneously engaged the force of the reciprocity rule and the contrast principle. Not only will my five-dollar request be viewed as a concession to be reciprocated, it will also look to you like a smaller request than if I had just asked for it straightaway.

Commitment and Consistency

  • It is, quite simply, our nearly obsessive desire to be (and to appear) consistent with what we have already done. Once we have made a choice or taken a stand, we will encounter personal and interpersonal pressures to behave consistently with that commitment. Those pressures will cause us to respond in ways that justify our earlier decision.
  • They (department stores) undersupply the stores with the toys they’ve gotten the parents to promise. Most parents find those things sold out and are forced to substitute other toys of equal value. The toy manufacturers, of course, make a point of supplying the stores with plenty of these substitutes. Then, after Christmas, the companies start running the ads again for the other, special toys.
  • Once a stand is taken, there is a natural tendency to behave in ways that are stubbornly consistent with the stand.
  • …people who have just asserted that they are doing/feeling fine–even as a routine part of a sociable exchange–will consequently find it awkward to appear stingy in the context of their own admittedly favored circumstances.
  • …be very careful about agreeing to trivial requests. Such an agreement can not only increase our compliance with very similar, much larger quests…”
  • …what those around us think is true of us is enormously important in determining what we ourselves think is true.
  • Whenever one takes a stand that is visible to others, there arises a drive to maintain that stand in order to look like a consistent person.
  • Persons who go through a great deal of trouble or pain to attain something tend to value it more highly than persons who attain the same thing with a minimum of effort.
  • Social scientists have determined that we accept inner responsibility for a behavior when we think we have chosen to perform it in the absence of strong outside pressures.

Social Proof

  • The principle of social proof states that one means we use to determine what is correct is to find out what other people think is correct.
  • In an ambiguous situation, the tendency for everyone to be looking to see what everyone else is doing can lead to a fascinating phenomenon called “pluralistic ignorance.”
  • A victim is much more likely to be helped by a lone bystander than by a group, especially if the people in the group are strangers to one another. It seems that the pluralistic ignorance effect is strongest among strangers: Because we like to look poised and sophisticated in public and because we are unfamiliar with the reactions of those we do not know, we are unlikely to give off or correctly read expressions of concern when in a grouping of strangers. Therefore, a possible emergency becomes viewed as a non-emergency, and the victim suffers.
  • We will use the actions of others to decide on proper behavior for ourselves, especially when we view those others as similar to ourselves.

What are the factors that cause one person to like another person?

  • Physical attractiveness
  • Similarity
  • Compliments
  • Contact and Cooperation
    • School desegregation is more likely to increase prejudice than to decrease it.
    • Because much of the heightened prejudice from classroom desegregation seems to stem from increased exposure to outside group members as rivals, these educators have experimented with forms of learning in which cooperation rather than competition with classmates is central.
    • The crucial procedure was the experimenters’ imposition of common goals on the groups. It was the cooperation required to achieve these goals that finally allowed the rival group members to experience one another as reasonable fellows.
    • The evidence that team oriented learning is an antidote to this disorder may tell us about the heavy impact of cooperation on the liking the process.
  • Conditioning and Association
    • There is a natural human tendency to dislike a person who brings us unpleasant information, even when that person did not cause the bad news.
    • (On intensely loyal sports fans who buy tickets to games they did not attend): Deep inside is a sense of low personal worth that directs them to seek prestige not from the generation or promotion of their own attainments, but from the generation or promotion of their associations with others of attainment.


  • It is the extreme willingness of adults to go to almost any lengths on the command of an authority that constitutes the chief finding of the (Milgram “shock”) study.
  • The paradox is, of course, the same on that attends all major weapons of influence. Once we realize that obedience to authority is mostly rewarding, it is easy to allow ourselves the convenience of automatic obedience. The simultaneous blessing and bane of such blind obedience is its mechanical character. We don’t have to think; therefore, we don’t. Although such mindless obedience leads us to appropriate action in the great majority of cases, there will be conspicuous exceptions — because we are reacting rather than thinking.
  • [On the extent of mechanical obedience to doctor’s orders]: (1) The prescription was transmitted by phone, in direct violation of hospital policy. (2) The medication itself was unauthorized; Astrogen had not been cleared for use nor placed on the ward stock list. (3) The prescribed dosage was obviously and dangerously excessive. The medication containers clearly stated the the “maximum daily dose” was only ten milligrams, half of what had been ordered. (4) The directive was given by a man the nurse had never met, seen, or even talked with before on the phone. Yet, in 95 percent of the instances, the nurses went straightaway to the ward medicine cabinet, where they secured the ordered dosage of Astrogen and started for the patient’s room to administer it.


  • …because we know that the things that are difficult to possess are typically better than those that are easy to possess, we can often use an item’s availability to help us quickly and correctly decide on it’s quality. Thus, one reason for the potency of the scarcity principle is that, by following it, we are usually and efficiently right.
  • The drop from abundance to scarcity produces a decidedly more positive reaction than does constant scarcity (i.e you value things more that have recently become more scarce).
  • Not only do we want the same item more when it is scarce, we want it most when we are in competition for it.
  • The joy is not in experiencing a scarce commodity but in possessing it. It is important that we do not confuse the two.

Very often in making a decision about someone or something, we don’t use all the relevant available information ; we use, instead, only a single, highly representative piece of total. And an isolated piece of information, even though it normally counsels us correctly, can lead us to clearly stupid mistakes — mistakes that, when exploited by clever others, leave us looking silly or worse.


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