Sam Gentle.com

Idempotent habits

I wrote before about "it's the opposite to the one I expect" as being a particularly useless way to remember something. The problem is that as soon as you internalise it, it's not true anymore; if you always turn the tap the wrong way, and you remember "I should turn it the opposite way than I normally do", that system becomes useless as soon as your idea of normal changes which, if things are working, should be really soon.

I've been thinking that there's a more general class of problems along those lines, which are non-idempotent habits. Idempotence is something you often talk about in software to mean something that you can do multiple times with the same effect as if you did it once. So adding 1 isn't idempotent, but changing your name to Steve is. You can change your name to Steve as many times as you like and you're still Steve, but if you add 1 twice you've actually added 2. Idempotence is often considered a sign of a well-designed system.

The reason I think this is particularly important for habits and other mental systems is that, unlike a computer, we tend to operate on patterns and associations. So a non-idempotent habit tends to stick around even when it's not useful anymore. I started using 24-hour time and one nifty shortcut I found was that in the afternoon I could just read the 24-hour time as the 12 hour time, by ignoring the first digit and subtracting 2. 1900 is 7pm, 1400 is 2pm, that kind of thing. The only problem is that I kept catching myself looking at 1900 and thinking "that's 5pm". I got so used to subtracting 2 that I was doing it twice!

That's a pretty innocuous example of how non-idempotent habits can get you in trouble, but there are others like "I'll try to be more assertive" that have similar issues. More assertive than what? Than you are now? That will change as you change to feel more comfortable with your assertivenes. Or if you tend to be really behind on things and you build habits to deal with that, those habits stop being useful as soon as they start working properly because you're not behind any more. The high water mark I wrote about before is another example.

Something all of these have in common is a certain degree of self-reference: the habit changes based on its own output. I think a better answer is to find fixed points of reference to anchor habits to. Instead of being useful at first and counterproductive later, an idempotent habit will stay relevant over time. That means less habits but stronger ones, because they have more time to build.