Influence, New and Expanded: The Psychology of Persuasion by Robert B. Cialdini
This is a fairly long book that details a few key principles of persuasions. The concept are very well illustrated with examples from well known figures as well as individuals. Examples include people using these as well as having these used on them. The use includes time when both parties benefit as well as those when one party clearly achieves advantage. There are also "scam" uses that can be identified so that you don't fall victim.
Many of the principles rely on variations of reciprocity. If you give somebody something, they often feel a need to give you something back. A free sample will often encourage somebody to buy something. Doing a favor to somebody will make them more likely to do something for you. Level-setting can be a variation on this. Giving somebody a lower priced option after starting higher gives them a sense of getting a favor from you. Sending cards or remembering other people helps make them more likely to do you a favor later.
People use "shortcuts" as clues to make quick decisions. High prices are often an indicator of quality and could encourage sales - especially if they are later discounted. Long lines also indicate something that is in demand. (This is one that marketers can often "game" by paying people to stand in line.) Expert appeals are also a common shortcut, even if the expert lacks expertise in the field. "TV Doctors" often pitch medical products - even while admitting they just play one on TV. A scientist's opinions are often valued by the public - even in fields outside their expertise.
Urgency can be used and abused. If it is the last item, you may be worried about the fear of missing out. (This is also an area that is often faked.)
People also like to be internally consistent. They have a desire to do something that is morally correct. Scammers can often take advantage of this to get people (especially elderly) to "correct" what seems to be a problem.
Group connection is another factor that can help persuade. In World War II, the Jews helped seek protection in Japan by appealing to their mutual history as "Asians". Salespeople will often do best when selling to people within their same group (whether it be ethnicity, religion, or even college attended.) Some salespeople are especially good at finding similarities to help sell. (This can also backfire if group is not quite right.) In one example, a door to door salesman would mention neighbors he sold to. He was able to further maximize by "matching". If he was selling to a couple, he would mention another couple. If he was selling to a housewife, he would just mention another housewife. This helped make the purchasers feel more willing to make the decision at the time.
The more commitments involved in a group, the greater the attachment. "Hazing" helps increase the ties to a group due to the work and challenge involved. Society now works at stopping hazing. However, this may just lead to it going underground or involving other ways to have this relationship.
The persuasion principles seem simple, but can be more complex in practice. The author gives many examples where he has fallen victim to persuasion tactics - even knowing that they exist. We may know various tactics, but it takes work to practice them authentically.
