PPUZZL

There is a chair in my apartment that I have sat in three thousand times. I know its squeak. I know which armrest holds the heat of a coffee mug and which forgets within a minute. I know the angle at which the light from the window crosses my notebook on a January afternoon. The chair is, in every measurable sense, the most boring object in my life. And yet, every evening when I sit down to work on a puzzle, the chair is the first thing my body locates.

What I am describing is a habit. What I am also describing is a puzzle — a small one, solved so often it has become invisible. Habits, like puzzles, are pattern-completion engines. They are the brain's way of asking itself the same question many times over until the answer becomes the question.

I came to puzzles late. I came to habits earlier than most. As a child I would arrange my pencils by length on the desk before I began my homework. The pencils were not, strictly, sharper for being arranged. But I was sharper. I had answered a small question before I asked a large one. The pencil arrangement was a puzzle I had built for myself, the way a beaver builds a dam — not because the river was wrong, but because the building of it was a kind of thinking.

In the lab they call this the "completion loop." Show a person a pattern with one piece missing and the dopamine receptors fire before the pattern is even complete. They fire on anticipation. The brain has learned that completing things feels good and so it begins to feel good before anything has actually been completed. This is, in essence, why crosswords work, why sudoku works, why the smallest jigsaw puzzle works, and why — if we are being honest — tidy rooms work too.

To love a puzzle is to love the moment before the answer. To love a habit is to love the same moment, just repeated until the love itself becomes the habit. Somewhere in the middle of this loop is the place where design lives. The puzzle designer's job is not to invent the answer. The puzzle designer's job is to invent the moment before the answer — the curve, the width, the colour, the silence — so that when the answer arrives, it arrives like a friend at the door.

My chair, in this sense, is a puzzle designer. So is my kettle. So is the slight wobble in the third floorboard of the hallway. They have all worked on me for years, quietly designing the moment before I do anything at all. The geometry of habit, it turns out, is not a straight line. It is a series of small invitations to begin again.