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In a previous post, I discussed the idea that believing that a self-help approach is plausible makes it more likely to actually help you. Basically, if a given book, or web page, or guru tells a convincing story, your belief in that story helps you to benefit from using their approach, regardless of what the approach actually entails. Another relevant piece of research, which came out this year, suggests that the same activity can be more or less helpful simply based on whether or not someone you trust has told you it helps ().
Why might this be? One obvious answer is that believing in the activity helps, and this is one more way to increase a person's faith that the activity will work - by extension, the activity then will work. However, I think there's more to it than that.
One possibility, suggested indirectly by the researchers, is that testimonials do more than simply tell someone the activity works. A testimonial explains, much more specifically, how it helped them. Hearing about someone else's experience helps the individual set specific and reasonable expectations for what they might get out of the activity. Setting reasonable goals is a very good thing for motivation. If a person is aiming to become happier and they don't believe that's changing your happiness is a real possibility, they won't try their hardest. They won't have faith in the activity. Ultimately, they won't benefit (Sheldon et al., 2010).
Further, providing people with concrete, attainable goals is important because recent research argues that having the wrong goal - specifically, aiming to be "happy," rather than to obtain some more concrete benefit, such as experiencing more gratitude or being more kind - can actually hinder you (Mauss, Tamir, Anderson & Savino, 2011). In this study, people who explicitly endorsed being happy as their goal were constantly disappointed with their own mood. They were never satisifed that they had actually managed to become happy. Testimonials serve as a possible vehicle for making sure that people avoid this pitfall - giving the individual specific outcomes to expect, rather than the wishy-washy and seemingly unattainable goal of constantly feeling great.
I think we're all used to thinking of testimonials as a marketing tool; some of the most satisfied customers (or even fake satisfied customers) sing the praises of a product so that people will buy it. However, a testimonial - at least a genuine one, that provides real, specific information to the consumer about what it looks like to improve using a particular approach - is much more important than that.
