In his new book, The Catalyst, Wharton business school marketing professor Jonah Berger offers techniques and strategies for changing minds. One strategy seems counterintuitive, but it’s brilliant: Effective persuaders don’t tell people what to do; they encourage people to persuade themselves.

According to Berger, if you tell someone what to do, they become defensive. However, if they arrive at the same conclusion themselves, they’re much more likely to buy what you’re selling, whether it’s your idea or product.

Here are four strategies to become an effective persuader and get anyone to follow your lead.