Principles of Persuasion – Part II

In the last episode I highlighted three of the six primary principles of persuasion – consistency, reciprocation and social proof. In this post I will look at three more – authority, liking and scarcity.

Understanding and employing these principles can help your business grow. As a consumer being aware of them can help you make better purchasing decisions based on what you need and want rather than what the seller needs and wants.

psychology and sales

How and why do these principles work?

The fact that we are susceptible to the principles of persuasion is a result of a psychological phenomenon known as ‘fixed-action patterns’. Fixed action patterns refer to certain, specific stimuli that trigger complicated series of behaviours.

What is interesting is that the stimuli needs only to be a single specific feature rather than the totality. What does this mean?

The animal sciences have contributed a large body of work to the study of these fixed action patterns and have laid bare how the most simplistic of triggers can initiate incredibly complicated sequences of behaviour.

For example; the mother Turkey, whose natural enemy is a polecat, can easily be made to ‘mother’ a stuffed polecat if it makes the right noise. Experimenters fitted a tape-player with a tape of the sound made by baby chicks to a stuffed polecat and  placed it in the mother Turkey’s territory. They discovered that the ‘mothering’ behaviour was initiated by the noise made by a chick and that the Turkey would mother anything that made that noise. This means that all the other cues were disregarded and that a highly complicated, long-lasting and intricate set of behaviours was instigated simply by the ‘cheep-cheep’ noise made by baby chicks.

This works in humans too – the word ‘because’ in a sentence makes people much more likely to respond favorably to a request than if it is absent.

This was concluded in a sociology experiment that tested the reaction of people to someone attempting to jump the queue for a library photocopier.

On three different days the experimenter tried to jump the queue by giving a different reason;

Day 1 – “Can I go to the front please?”

Day 2 –  “Can I go to the front please because I’ve left my baby in the car?”

Day 3 – “Can I go to the front please because I have to photocopy these papers?”

One would intuitively expect that the request was met most sympathetically on day 2 because there is a good reason why the person would not want to wait around for a long time. However experimenters found that there was no significant difference between responses on days 2 or 3.

The conclusion is that the important factor is that a reason is given – the reason itself is fairly irrelevant as long as there is one!

So, when constructing your call-to-actions on your website or marketing material always give a reason for the action you want people to take. It doesn’t matter what it is, just give a reason and you will get a better response!


Principle 4 – Authority

Authority is a powerful emotional trigger – society is founded on the obedience to authority and without it there would be anarchy! Interestingly though, it seems that “we are often as vulnerable to symbols of authority as to the substance.”

This statement shouldn’t come as a shock to anyone who has over the years watched TV ads for products such as washing up liquid, shampoo & conditioner, stain removers, etc. These products will often use the power of authority to subconsciously drive home their message and to convince the viewer that their marketing messages are scientific facts. This, at a basic level, is done by dressing an actor in a white lab coat. There are other visual indicators, but the white lab coat instantly delivers a stream of information to our subconscious that makes us more likely to believe the claims that are made.

The powerful effect of authority and assumed authority was brutally demonstrated by sociologists like Stanley Milgrim and Phillip Zimbardo who were able to get unwitting subjects to go as far as to seriously injure and even kill people as they obeyed instructions from a ‘scientist’ in a lab coat, or inflict a brutal regime of discipline and punishment upon volunteer subjects based on the ‘role’ they were playing in an experiment.

By leveraging the principle of authority in your marketing you can remove doubts and increase sales of your products. This can be done by becoming the authority yourself, or leveraging a third-party’s authority on your behalf.

Principle 5 – Liking

If you have ever been to business networking events you may have heard the expression – ‘meet, like, know, trust’ – which neatly encapsulates the process of doing business with someone. People buy from people is a cliche, but the real maxim is that people buy from people that they like.

To give a basic example – if you could get exactly the same product from two different people, one whom you liked and one whom you disliked, who would you buy from? Obviously from the person that you liked.

The famous US defense attorney Clarence Darrow once said “The main job of a trial attorney is to get the jury to like the client” knowing that it is much harder for people to convict someone of a crime if they are likable.

The Tupperware parties that used to be so popular and have morphed into Ann Summers or Cosmetic product parties work on the same principle – the person invites their friends to the launch party as they are more likely to show up and buy stuff than acquaintances or strangers.

What are the factors that instigate ‘liking’?

  • physical attractiveness
  • similarity
  • flattery

What is interesting is that the principle of liking still works even when someone knows they are being flattered – that is, it doesn’t have to be true!

In the Guinness Book of Records there was a car salesman called Joe Giroud, During the 1970’s Joe earned $200,000 a year as a salesman. he was the number one salesman for 12 years running as he sold an average of five cars a day, every day.

One of the secrets to his success was the fact that he sent a greetings card to everyone of his customers each month  with the message ‘I like you’. When asked for the secret to his success he used to reply “A fair deal and I make them like me.”

Principle 6 – Scarcity

The principle of scarcity works on the basis that we want what we cannot have. Experiments have shown that particular toys become more attractive to children if they are told that they are not allowed to play with them. You probably have experiences in your own life that back up this finding.

The principle works the same in sales and marketing too. By making something scarce it becomes more attractive and desirable. This is why limited editions, temporary sales and the like are so prevalent and so effective.

What is interesting about this principle is that experiments have shown that the prospect of losing something is more powerful than that of ‘gain’.

Prospects become more likely to buy an item that they have previously viewed if it appears that someone else is interested and thus there is a strong possibility of that item becoming unavailable. Anyone who has ever bought a house or a car will have first-hand experience of this principle.

It is possible to create scarcity in your sales and marketing by running sales, by offering value-adds to the first number of buyers or by simply only stocking a set number of items.



We are all at the mercy of psychological triggers of persuasion and are bombarded with them constantly both via media and when we are out and about. If you can effectively work some of these principles into your marketing then you will sell more stuff! Similarly if you are aware of them as a consumer then you will be less influenced and will make better buying decisions.

For help incorporating these principles into your online marketing please call Robert at Lead Generating Websites on 01708 208 889

Action Steps

Use ‘because’ and give a benefit as a reason in your call to actions


Marcus Welby

Authority is easily developed – in fact you already are an authority if you run your own business – you can communicate that to prospects through use of content on your website and other platforms.

That doesn’t mean that you have to produce content regularly, although if you do that would be great, it can just be one piece of comprehensive, useful, relevant content that you can repurpose into different formats and syndicate to various outlets

You can also convey authority by the clothes you wear, the company you keep and the way you present yourself online.


Start thinking about how to get your customers and prospects to like you – if you were to send your customers a Christmas card, a birthday card every year that would force them to like you more – it is also a good marketing ploy as it keeps you in the forfront of their mind.

When you go to events don’t try to sell but make it your goal to make people like you and want to connect with you. You can do this online too with video, or just through email or social media marketing.

The key is to set your goal and then map out and implement the action steps to reach that goal – so for liking it would be to be pleasant, helpful, complimentary and honest.


Think about how you can introduce scarcity into your sales funnel – this could be by offering special deals for a limited time – we just had black Friday which is probably the best example of scarcity marketing around at the moment – people will literally trample over their fellow human beings to get the best deals. It’s actually quite frightening – but how wonderful would it be if that was your shop every morning!!!!