Wow, this was one of the better books that I have read recently – and finally after hearing about it on a lot of ‘top book’ lists by some of the people that I follow, I decided to really dig into this book and finished it within an afternoon.

This book taught me a lot about how to persuade people. It breaks down influence or as Robert calls it “weapons of influence” into six different weapons:

  1. Reciprocation
  2. Commitment and consistency
  3. Social proof
  4. Liking
  5. Authority
  6. Scarcity

In each of the chapters, he provides numerous anecdotes, case studies and experiments that describe what the ‘weapon’ is, how it is used and why humans fall susceptible to the weapon. Perhaps my favourite part of the book is a small section at the end of each chapter which describes “how to say no” – i.e., how to defend yourself against these weapons of influence when you may (or may not) know that it is being used against you (and in this context, to persuade you to do something that you may not have wanted to do).

Here is what I learned from the book:


This ‘weapon’ is that feeling or urge that you might feel when someone (could be a friend, acquaintance, stranger) gives you something and you feel that you have to give something back. Robert talks about a few instances where this is done to get something from you – for example, there are people that hand out flowers to you and then ask you for donations. If you unfortunately take the flower, you will certainly feel the urge to give something back and since the flowers cost almost nothing, those people are essentially using this trick to get you to donate money.

In this chapter, I also learned an interesting trick used in sales – if you have differently priced items and want to sell higher priced items, you should walk through your items from highest price to lowest price (as opposed to lowest price to highest price). This is based on the idea that we feel bad rejecting offers and so after a while, we tend to be more accepting if we have rejected multiple times previously.

How to say no to reciprocation

The challenge in saying no is that there are some people who do not use this trick maliciously – they really want or need a favour from you and are not looking to take advantage of you in any way. So you really cannot just refuse all requests. But then there are times where if you are too nice or polite, the people take advantage of the influence of reciprocation and may ask you to do something that you really do not want to do. The trick then is to recognize when someone is offering you a nice favour and when they are using the reciprocation weapon against you. If the former, accept. If the latter, recognize that it is not a favour but actually a trick – that way, you won’t feel like you have to reciprocate against a trick.

Commitment and consistency

In this chapter, Robert talks about how he was trapped by a very pretty young woman. The young woman was conducting a survey and Robert, trying to impress her, gave out answers that were consistent with the image that he was trying to portray (that he had a lot of money to spend, that he dressed well, etc.). But as the woman asked different questions and led him down a path, he was suddenly asked to purchase season tickets to the opera. Robert felt trapped because to remain consistent with the image that he had presented before, he had to buy the tickets.

What are the tricks in commitment and consistency? If you want someone to say yes to your request, ask them to commit to a smaller request first. For example, studies showed that people were more willing to commit to volunteering if they first answered a survey about spending time collecting money for a charity. First, they would answer the survey and then in a subsequent call by the charity would get their commitment.

Another trick? Callers that ask for donations may ask you “how are you doing today?” or “how are you feeling this evening?” and if you reply with “good, thanks” then you would find it awkward to not help out the unfortunate victims of some sort of terrible act of nature.

And you probably know this one already but writing something down is a stronger commitment device than saying it out loud verbally.

Yet another trick – be wary of the low ball approach. Sometimes, dealerships, shops, websites will try to get you by providing something heavily discounted – to the point where they may even be losing profit on the item. But once they get you to commit to the item, they may bump up the price to something fair or ‘forget’ to add on or include add-on items (for cars, this could be packages like air conditioning, leather seats, etc.). But once you’ve committed, you are less likely to back out on the item (even if the price significantly increased after).

How to say no to commitment and consistency tricks

Much like other ways to say no, this requires quite a bit of self awareness. Robert’s advice is that whenever you feel like you are doing or accepting something you do not want to do – pause and assess the situation. If you could make the same decision again with the information that you have now, would you? If not, leave.

Social proof

I remember a while ago that Shawn Kanungo and I recorded a podcast about this idea of how much value we derive from reviews. We go on Yelp or we go to look for that plumber or air condition service and we look at reviews, not even looking at anything below 1 and 2 stars. But how much credibility can we give these reviews. Shawn shared a story about a ‘restaurant’ in the UK that was on Yelp, posted a lot of photos but did not let anyone eat there. It had a long ‘waiting list’ when it was actually not a restaurant and everybody started leaving 5 star reviews saying how amazing it was there even though nobody had actually eaten there.

Tim Ferriss often likes to follow a quote that I’m sure I’ll badly butcher but in short, when you find yourself in the majority, it’s time to stop and think.

How to say no to social proof

From time to time, I like to try restaurants that may not have the best reviews but maybe a friend I trust recommended it to me. Other times, you have to think about the social proof that something has (say reviews). Could those reviews have been paid reviews? Or reviews that were not completely objective? If so, you have to re-think what those reviews mean to you because if a restaurant has a lot of paid 5 star reviews, it may not actually be that good.


Ever notice that we seem to like people that are more attractive or smarter or even dressed well? Strange isn’t it? But people use this weapon all the time. Think about those snazzy management consultants that come in dressed in three piece suits, a brilliant tie, pocket square and funky socks (okay, that might be describing me). Think about if a bum who was dressed in ragged clothing came up to you or if a man in a suit came up to you, who would you give the time of day to?

Robert explains that we generally say yes to requests from people that we like or are similar. I know I’ve done this before – when choosing what kind of foods to eat, I’ll generally choose Chinese food. Heck in elementary school, I was friends with a lot of people in the class but my closest friends were all Asian.

How to say no to liking

Robert has an interesting tactic to combat the ‘liking’ weapon: he says to ask yourself, after a bit of time, if you have come to like someone or something more than you expected. If for example, you meet someone at a business conference for a few minutes but find that you really, really like them, it’s probable that the ‘liking’ weapon has influenced you.

If you recognize that this has happened, here’s the next step: separate the person from the transaction. If that person then tried to sell you some services, think about the services alone – is this something that you need? Would want to buy? Yes, this may be difficult to do but remember that you are not buying the person you like, you are buying a product or a service. Just because you like a car salesman does not mean that you can buy the car and have the salesman come home with you.


Thinking about this weapon, I have probably fallen for this many, many times. I see advertisements that talk about ‘experts’ who recommend different products. I see other consultants around me at client sites touting their expertise to the client (in well dressed suits and business attire no less).

Do you work in the service industry?

A great mini story was shared here by Robert on a waiter that he observed at a restaurant. He noticed that this particular waiter was earning far more tips than other waiters and he wanted to know why, so he observed him over several nights to see what particular things that he did that was so special.

  • For couples on dates, he would focus on the man, intimidate him into ordering and tipping lavishly (to impress his date)
  • For families, he would talk a lot to the children, often being super happy and friendly to everyone
  • For older married couples, he would be respectful and talk to both of them equally
  • For people that were dining alone, he would be friendly and chatty
  • For larger parties, he had this great trick that would help make him an authority to the parties’ eyes – whatever item the first person chose, he would say “I’m afraid that is not as good tonight as it normally is. Might I recommend instead the __ or the ___. They are both excellent tonight”. The items that he ended up recommending were slightly less expensive than the first item that the person chose.

** With this last maneuver, he actually used several principles of influence: the waiter appeared to have done them a favour by offering valuable information, people would then feel grateful and want to reciprocate with larger tips. The waiter also appeared to be an authority and therefore, when it came time for wine pairings or dessert, he would then recommend pricier items and not appear to be taking advantage of the parties because previously, he had recommended items that were less expensive.

How to say no to authority

Whenever you feel like you are being influenced by the weapon of authority, ask yourself two questions:

  1. Is this authority really an expert?

The man could be a doctor, lawyer, judge, etc. and in those cases, yes, they are really experts. But some people are touted or advertised as experts when they really are not.

  1. How truthful can we expect the expert to be here?

Depending on the situation, they may be truthful and they may be adjusting the truth. If a doctor appears in an advertisement and is trying to sell a specific brand of medicine, I think you can recognize that the doctor does not have to be truthful here. If the doctor is with you as the patient and trying to convince you to do a certain procedure, you can expect that they have your interests at heart.


Limited edition. Tonight only. Items are selling out quickly. Any time we feel like an item is rare, limited or that only a few are available, we feel the pull of wanting the item. Robert talked about his brother who sold cars by asking all the potential buyers to come at the same time. He would then have customers wait one by one to inspect and think about buying the cars but the pressure of having other customers waiting for them to make a decision would often get them to buy without negotiating hard often because the customer would think that they would lose the chance to buy the car if they did not pounce on it then and there.

How to say no to scarcity

First, think about the item itself. Are you buying it because of its rarity? Rookie hockey cards? Toys that are sold out? It’s okay to buy items if they are rare.

But realize that there are certain items that do not change (i.e., you do not enjoy them more), if they are rare. For example, buying a rare laptop does not mean anything because you can get a laptop anywhere and just because it is rare does not mean you will enjoy using it more. Buying a limited edition cellphone? Again, you can use any cellphone to make calls so having a limited edition cellphone does not make you enjoy the cellphone more (I would think). Recognize when you are buying something for its utility.

If you understand these weapons of influence, you are going to be much better equipped at recognizing when those situations are happening to you and more importantly, how to combat those weapons in an effective manner.

About the author:

Wang is a management consultant, self-published author, Distinguished Toastmaster, co-host of a podcast, Udemy teacher, former Uber driver and all around hustler. He is also obsessed about books and he reads books so that you don’t have to. Want a list of Wang’s top ten formative books in his life and career? Interested in book summaries and recommendations every month? Subscribe to Wang’s e-mail newsletter!