You wonder whether such a structure of thought—which, like any structure, also has its entrances and its thresholds—might ever actually become coextensive with a building: whether it would be possible for a thought structure and a physical structure to overlap. If an occupant lives a long enough time alone in the same building, and if his mental layout is gradually scaffolded over the rooms in which he thinks—then yes, you decide, eventually the two structures will grow concentric. If you step over the threshold of that building, you pass over the threshold into its thoughts. Crossing the entrance of that building, you are entranced. And if the thought structure happens to be a mad one, then you must move from room to room in that madness.

You really are living inside a madman’s thought structure, you realize, and his madness’s mansion has many rooms. In a spasm, you clutch at the bedsheets with your fingers. Your brain is racked by a black panic. Sitting up, you survey the empty room around you. It seems to reel, spinning as if you were drunk. Beneath the baseboards, behind the joists, you can visualize—as in an X-ray—a cage of translucent gray lines, shadowed like bone. And when your temples throb, you can feel the room driving itself into your mind. You can feel the cabin and its thought structure hammering away, driving itself deeper inside. It will go on pounding for as long as it takes, you know, until finally you internalize it, introjecting all the owner’s psychical architecture. Then your mind will mimic the layout of that madman’s mind completely. Like two apartments in a complex, your mind and the owner’s mind, mirror images of each other: two insanities sharing a floor plan.

Gritting your teeth, you clench your eyes violently, as if trying to crush something between cheek and brow. What you are trying to crush is every throbbing thought in your skull.

In the morning you take a walk through the backyard, cutting a wide berth around the field’s middle. You have not slept all night.

It is a cool morning, dim with impending sunrise. For a while you are able to admire the dawn. Lying on a slope just three hundred feet beneath the timberline, the backyard commands an eastern prospect of declivitous pine grove and horizon, and, staring ahead, you can see clear out across the forests. The woods stretch forever away and down, black avalanche bristling the foothills. Above the dark margin of the lower fir forests is an argent margin of overcast, and at the border dividing them is a thin interstice of gold light. You listen as a breeze insufflates the pine trees. Even at this distance you can hear it, a hissing like water sizzling all over the mountain. You turn to head back toward the cabin, and at this moment a strong wind blows, giving the pines to sough again. Suddenly the sound is hateful to you. For now that hiss reminds you not of water sizzling, but of the noise a threatened spider makes: a circumambient, mandibular sound, sibilant, as if the entire mountain is hissing in your ear. The wind picks up, and the hissing intensifies. It engulfs you. You hurry back to the cabin to escape the wind, and as you walk you keep your eyes fixed on the porch and your hands cupped tightly over your ears.