The decision

This chapter asks you to decide something. It comes late because at the start it would have sounded like the advice you've always been given, which is to stop checking. By now you've seen why that advice never landed, which is that the checking seemed like care, and why it's right anyway. Rechecking fades the picture and makes doubt. Going over it in your head is a recheck. The doubt is about the fade and not the door. The feeling of certainty isn't a measurement. The calm is short and grows the doubt. And the once, done with attention, is all the care the door needs.

Here's the rule I'd suggest. Put it in your own words if you like.

I check once, with attention, and then I let the doubt be a feeling and not an instruction.

It has five parts, and each answers a chapter.

I do the once properly. Slow, with the senses, at the moment of doing the thing. I say it aloud, with the time.

I don't go back. No walk to the door, no photo, no app, no asking, no sent folder.

I don't go over it. The replay is a recheck. When I notice it starting, I reach for the sentence and turn to something else.

I let the doubt come and go. I name it, I sit through the few minutes, and I let the world's evidence count when I get home and everything's fine.

If there was no once, I go back and do it. One attentive check, not zero. That's the exception and it's part of the rule.

It helps to plan for the moments when the habit will try to restart. Peter Gollwitzer and Paschal Sheeran pooled ninety-four tests of plans in the form "when X happens, I'll do Y" and found that they make people more likely to follow through. A plan like this works because you've decided what to do before the moment comes. Three are worth writing down.

When I'm halfway to the car and the doubt arrives, I'll say the sentence aloud and keep walking.

When I notice myself replaying the check in my head, I'll say "that's a recheck" and turn the radio on.

When I've sent an email and my hand goes to the sent folder, I'll close the program and start the next job.

I'll be honest about what to expect, and this is my expectation and not a finding. The first week will feel careless and slightly frightening. The doubt will be loud, and you'll go back a few times, and you'll spend some drives in a state you'd rather not be in. The second week it'll be quieter. Someone may notice you leaving the house without the usual circuit and say something, and you'll mind it.

Against that, you should find within a fortnight that the doubt is shorter and fainter, because it's not being fed. You should find that you can remember locking the door, because you're doing it once with attention instead of four times on autopilot. The mornings should get back the twenty minutes the habit had taken. And at some point you'll be at the lights and notice that you're thinking about the meeting, not the straighteners, and that will be the first morning in years that started with the day and not the door.