"Once I've decided, the how will follow"

Here's the belief chapter 2 said the book would examine. Deciding is the hard part. Once you've truly decided, the doing takes care of itself, the way it does when you've decided to catch a train. You don't need a plan to get to the station. You just go.

Paschal Sheeran and Thomas Webb reviewed the research on what they called the intention-behaviour gap in 2016, and their opening line is that both bitter personal experience and meta-analysis agree that people don't always do what they intend to. The review goes on to ask how large the gap is, when intentions get carried out and when they don't, and what closes the gap. I'll be careful here because I read the summary and not the full paper, so I won't quote figures. What I'll say is that the existence of a well-studied gap between deciding and doing is not in doubt, and that the people who study it don't think deciding harder is what closes it.

What does close it is best seen in a single experiment. Sarah Milne, Sheina Orbell and Paschal Sheeran took 248 people and gave one group a motivational intervention designed to make them want to exercise, using a well-known theory of health motivation. It worked, in the sense that it raised their sense of threat, their sense that exercise would help, and their intention to exercise. It didn't raise their exercise. A second group got the same motivation plus one more thing, which was to write down when and where they would exercise in the coming week. That group's exercise rose sharply. And the plan didn't change their intention or any other measure of motivation. It changed only what they did.

That's the train. When you decide to catch a train you already know where the station is, what time the train goes and what you'll be doing at ten to eight. The decision is easy to carry out because the how is already in it. The wish has no how in it at all. "Get fit" has no station, no time and no ten to eight. It's a decision about a destination with the journey left blank, and on a Tuesday the blank is what you meet.

The when-then form of the plan, which Milne's participants used and which this series has used in every book, is the subject of chapter 18. For now the point is only this. The how doesn't follow from the decision. The how is a separate thing you have to write, and if you don't write it, the Tuesday writes it for you, and the Tuesday always writes "tomorrow".