Although most advice on writing to persuade focuses on emotion, including my previous post, would-be persuaders also need to know how to wield logic. Especially if they need to overcome skepticism, as in homeopathic cures, or build trust, as in investment advisers.
So while the heart may be a key sticking point when it comes to persuasion, don’t forget to talk to the brain too. You can make your case in two ways:
1. cite specific cases that lead your reader to a general conclusion, e.g. 90 per cent of the 1,000 people who consumed less than 1,000 calories a day for a week lost more than five pounds
2. argue from a generally accepted statement to a specific conclusion. e.g. calorie restriction leads to weight loss, so I should eat less
The specific-to-general approach works only if skeptics can’t take serious issue with your conclusion. For example, if the dieters also worked out for an hour each day, you could not insist that the weight loss was caused mainly by the calorie limits.
So be careful that your evidence and conclusion can bear the weight of close scrutiny.
Even if your case is strong, you may be wise to also explain why. For example, with the weight loss argument you could simply explain how burning off more calories than you consume produces weight loss.
Here, you have to make sure your explanation is clear and accurate. A teeth whitening ad that’s been popping up all over my internet lately pretends to provide a scientific explanation, but the over-blown wording quickly told me it was bull. It talked about “powerful oxidizing solutions” that “penetrate the porosities in the rod-like crystal structure of enamel and oxidize interprismatic stain deposits.” Dentists, correct me if I’m wrong.
One of the reasons content marketing is overtaking the hard-sell tactics of the teeth-whitening ad and its ilk is the growing sophistication of consumers. We want not only examples of how your product, service or expertise has helped others, but we also want to understand why.
Products like the teeth whiteners, from an alleged mommy blogger, may sell well at first because ad saturation lets them find enough stupid or desperate people. But they don’t have the strong legs of products and services with claims can be backed and explained.
There may have been a fool born every minute in P.T. Barnum’s time. But with today’s sophisticated consumers and the ease of googling suspect claims and critical product blogs, people who are in business for the long run are best to assume that their readers are smart and skeptical.