The principle of social proof states that people follow the lead of others who are similar to them. They look to those around them for cues on how to behave, with peers giving the most powerful cues.

The most famous examples of social proof in copywriting are headlines along the lines of ‘Ten million housewives can’t be wrong’, which position a product as the preferred choice of the majority – and therefore of the reader too. It is, of course, a non sequitur – the argumentum ad populum (‘appeal to the people’) that suggests that if lots of people believe something, it must be so.

The King deploys the argumentum ad populum on the cover of his 1959 hits compilation

A classic and much-used example is selling a product on the basis of its being the number-one seller, or promoting a company on the basis of its being the leader. The saying ‘nobody got fired for buying IBM’ encapsulates the appeal of going with the majority.

Social proof can have quite a powerful emotional sting. Recently, a door-to-door canvasser for the RSPCA told me that ‘lots of people’ in my ‘animal-loving neighbourhood’ had signed up for regular donations. The inference being that if I didn’t, I’d be some kind of animal-hating outcast. 

In the examples above, the copywriter is actually imparting the information to support their position. But in the age of Web 2.0, the consumer is much more likely to go out and find such information for themselves. If customers want to know the views of their peers, they don’t have to look much further than Twitter, Facebook, Amazon, the iTunes store or any of the myriad other channels where consumers share views and information. As a result, marketing messages have less authority and may simply be disregarded. 

However, there’s still room for copywriting based on social proof. Think about where your customers look for advice or guidance, and how you can emulate the tone or nature of that content. Testimonials and case studies are enduringly powerful, particularly in B2B marketing, and they allow the copywriter to shape, edit or subtly direct what is said so that it highlights the benefits of a product or service. In B2C marketing, there’s a clear trend towards using real or mock-real figures in TV advertising and elsewhere, or documentary styles, to give a sense that the reader or viewer is directly accessing the views of their peers.

As long as the information feels trustworthy, the audience will still respond – remember, many people actively desire the reassurance of running with the majority, so as long as your message is consistent and clear, it’s got a good chance of succeeding.

I am a hetero male. I like attractive women. Therefore I will buy this technology magazine

Persuasive copywriting is a matter of exploiting a number of proven, well-established principles. Those who persuade well know how to appeal to particular human desires and needs. By understanding these needs and appealing to them, we can become more persuasive copywriters. The principles are taken from the work of management researcher and writer Robert B. Cialdini, who spent decades identifying what makes some people better at persuading than others.

The first principle I’d like to focus on, liking, states that people like those who like them, and are more likely to follow the suggestions of people they like. Similarities between people in terms of views, preferences and perceptions make them like each other, and people also like those who praise them, whether or not the praise is merited.

The principle of liking is clearly seen in adverts that deploy an attractive face to promote a product. Research shows that we generally like good-looking people more, and are more likely to respect their opinions.

Cialdini himself cites the example of Tupperware to illustrate the principle of liking in action: the product being sold in the home, face to face, via a warm, friendly relationship between vendor and customer. But copywriters, by definition, don’t get to meet their audience and strike up a friendship with them. How can we apply the principle of liking in copywriting?

One way would be to write a headline or introduction that sets up a friendly rapport with the reader. Instead of beginning with the benefits of the product or service (as we would normally do by default), we can subtly align ourselves with the reader by suggesting that we have things in common, or giving them a compliment. For example:

If you’re a parent, you already know how to manage your time, deal with difficult people and juggle priorities. Now here’s a way to get rid of at least one of your worries…

By demonstrating knowledge of the reader’s situation, we indicate that we are like them; that we understand them. And because we’re implicitly praising them too, we hope they’ll warm to us as a friend. Copy like this marks out common ground between the copywriter and the reader, using the reader’s recognition of details from their own life as the key. This sets the scene for a marketing message that, because it comes from someone who is both ‘like’ and ‘liked by’ the reader, is more likely to be acted upon.

Of course, it’s easy to get wrong. The setup needs to be convincing – which means writing it from first-hand knowledge or rock-solid research rather than a five-minute scan of a Wikipedia page. It also needs to be sincere, insofar as a mass-communicated message can be sincere. (See my earlier post on sincerity, tone and attitude in copywriting.) The whole message needs to be congruent, with content, tone of voice and presentation all working in harmony.

There’s no need to do too much; often, a lighter touch works better. People will warm to those they have just met, as long as they feel there is some kind of link or common ground. Very small similarities or shared interests are enough to generate rapport. We know this from real life, where even the most distant common acquaintance will make us warm to someone we otherwise know nothing about.

Finally, note that while we like those who praise us, we dislike those who convey negative information. This ‘shoot the messenger’ tendency has important implications if you’re going to use scare tactics in your copywriting: by bringing bad news to the reader’s door, you associate yourself with it – even if it establishes your knowledge of their situation and you then go on to offer friendly advice.