Methods of Persuasion by Nick Kolenda explains several psychological techniques that can be used to subtly influence people. Psychologists and salesmen have known about many of these techniques for decades and I’ve heard of most of them before, so I didn’t feel like there was really anything new here, but it’s nice to have everything all in one place.

If you want to convince somebody to do something, you should start by priming them. For example, if you want someone to be more open-minded, you should start by telling them an anecdote about someone being open-minded. Something like, “I used to hate  the idea of eating Brussels sprouts, but then I tried them and ended up liking them a lot.” The person will start thinking about times they tried new things and this will make them more open-minded to your suggestion.

Getting someone to think about politeness makes them more polite, getting someone to think about friendliness makes them more friendly, etc. This reminded me of something a co-worker told me about his wife always being in the mood after watching romantic comedies or studies that show people are more aggressive immediately after playing a violent video game. I think most of us already know this instinctively. You never want to tell someone something that will make them mad when they’re already in a bad mood. You want them to be in a more pleasant mood, so your bad news won’t be as much of a big deal to them.

Another persuasive technique is called anchoring. It’s an old sales technique to start with a high number (this toaster is worth $1000) then lower the number to make someone think they’re getting a good deal (but we’ll let you have it for $50). The person will think they’re getting a better deal than if you just started with $50. Anchoring also works in courtroom situations. Judges are more likely to give lengthier prison sentences if the prosecutor starts by asking for a higher number than if they ask for a lower number. It’s human nature to start from the number we’re first presented with and adjust up or down from there.

Another form of anchoring is the contrast effect. Men are more likely to rate a woman as being more attractive if they’re comparing her with less attractive women and vice versa. The contrast effect also works with food. People will estimate that a cheeseburger has more calories when comparing it to a salad, and less calories when comparing it to a cheesecake. So you can manipulate people by providing a contrasting example.

If you ask someone to estimate Gandhi’s age after first asking if he was older or younger than 140, people will guess ages closer to the older side. Throwing out numbers, even ridiculous ones, influences people’s judgments.

Another anchoring technique is the decoy effect. When selling a product, it’s always a good idea to have a ridiculously priced luxury model. Not many people will purchase the luxury model, it’s just there as a decoy to make the standard model seem like a better deal. By simply offering a higher-priced version of something, you can sell more of the regular-priced version.

You can use this in day-to-day life as well. When making a request from someone, first start by asking for a big favor they’re not likely to say yes to, then follow up with a smaller request. They’ll be more likely to say yes than if you only asked for the small favor by itself.

Another technique is to convey high expectations. When people have high expectations for something, they’re likely to change their perception to match their expectations. We tend to see what we expect to see and feel what we expect to feel. For example, people enjoy cheap wine more if you trick them into thinking it’s expensive wine. The wine will actually taste better to them just because they’re expecting it to. Sometimes our expectations can even lead to a self-fulfilling prophecy. If we expect something to happen, we may cause it to happen ourselves.

People form opinions quickly, so what you mention first will influence everything else you have to say. In order to be your most persuasive, you need to create a strong first impression.

I was most skeptical of the section on body language. He makes the claim that when people cross their arms, they’re more likely to be close-minded, but according to an episode of the Skeptic’s Guide to the Universe, this isn’t true. He at least acknowledges that trying to influence people based on body language isn’t practical.

When someone’s attitude is inconsistent with their behavior, they experience cognitive dissonance and try to resolve the inconsistency. So if you want someone to comply with a large request, start by asking for a small request (such as a door to door salesman asking for a glass of water). Once you say yes to a person once, you’re more likely to say yes to them again.

Even simply asking someone how they’re doing can increase compliance. Most people will automatically say they’re doing good as this is the social norm. They’ll then be primed to say yes to your request in order to remain consistent with the positive attitude they just expressed.

Applying social pressure is another way to manipulate people. In studies, people will give the obviously wrong answer to a question if several people before them give the wrong answer. This is because we don’t like to go against the crowd. In this chapter, he unfortunately repeats the debunked story of numerous people watching the murder of Kitty Genovese without doing anything to help her. In reality, not that many of her neighbors were aware of the attack and a couple of them did call police. He could have avoided repeating this myth by doing a quick internet search. Despite this error, the underlying point that people will often do nothing when a situation is ambiguous in order to avoid social embarrassment is a valid one.

A study showed that people are more likely to litter when there’s already litter on the ground. Social norms like this can be leveraged in your favor. For example, if you put dollar bills into a tip jar, customers will be more likely to tip with cash rather than coins. Also, when you do a favor for someone, they will feel social pressure to return the favor. If you compliment them, they’ll feel pressured to compliment you back. Another old salesmen technique.