"I'll just ask, it's no trouble"

There are rechecks that don't look like rechecks. "Did I lock the door?" said to your partner in the car. A photo of the hob taken on the way out, to look at later. The app that shows the smart lock is engaged. Texting home to ask someone to look. Each of these feels like a sensible modern alternative to walking back, and each is the recheck by another route.

Take asking. Chris Parrish and Radomsky interviewed people who seek reassurance and check repeatedly, and found the two go together, and that people with a diagnosis sought reassurance about the same kinds of threat they checked for, fire and theft among them. Asking your partner is checking by proxy. It works the same way, gives the same short calm, and has an extra cost, which is that your partner is now part of the loop. They say yes, you locked it, and they've learned that the question will come again tomorrow, and they've begun, without meaning to, to watch you lock the door so that they can answer. Your doubt has become their job. The kindest thing they could do would be to stop answering, and the kindest thing you could do is stop asking. Chapter 21 has a form of words for both of you.

Take the photo. It seems clever. A picture of the hob, taken as you leave, settles the question for good. Except that the photo has to be looked at, and looking at it is a check, and the fade applies. You look once and feel fine. You look again at the lights, because the doubt has arrived, and the photo now seems ambiguous. Is that dial on zero or just near it? Was it taken this morning? You've moved the checking from the kitchen to your phone, and phones are always with you, so the checking can now happen anywhere. The same goes for the app that shows the lock. It's a handle you can push from your desk, and you will.

The deeper problem, and this is my own reasoning, is that all of these keep the question open. A check that ends with you leaving and not looking back is a closed question. A photo, an app or a partner who'll answer is a question that's still available, and the doubt, once it knows a source of relief is available, will go to it. Every proxy is a door you can go back to.

So none of the proxies is a way round the habit. They're the habit with better technology. The way round is the same as it always was. The once, done properly, and then nothing. No photo. No app. No asking. Your partner will be relieved.