How to stop overthinking, when more thinking is the problem

Do we sell the house to fund the venture, or is that conviction talking when it should be fear?

Question 20 of the Index

You have been round this one enough times to know the shape of it, and the going round is the part that feels like work. It is eleven at night and you are running the same three scenarios you ran at lunch, arriving where you arrived at lunch, and calling it thinking because it is exhausting and it is about something that matters.

Overthinking is not too much thinking. It is thinking that has stopped taking anything new in. A thought that goes somewhere costs you something the first time you have it, and less the second time, and by the ninth it costs nothing at all, which is how a loop can run for four hours and leave the question exactly where it was at the start.

The test is cheap and slightly unpleasant. Write down what you concluded the last three times round. If the three are the same sentence, you are not deciding, you are rehearsing, and the rehearsal is doing a job for you: it keeps you close to the problem without requiring anything of you. That is not a flaw of character. It is what a mind does when the next step is expensive and the circling is free.

What breaks it is almost never more thinking. It is a question you have not asked, and you have not asked it because asking it commits you to something. Not what should I do, which you have now asked two hundred times, but what am I protecting by not deciding, which most people have not asked once.