Finished three unrelated books this month and they turned out to be arguing the same point from different corners: that attention is a practice rather than a resource.
The resource framing is everywhere — attention is spent, captured, stolen, budgeted. It is a useful metaphor for selling things and a poor one for living. A resource is depleted by use. A practice improves with it.
The photographic version of this is obvious once stated. Nobody has ever looked at a street carefully for an hour and come away with less capacity to look. The hour is tiring in the way that walking is tiring, not in the way that spending money is.
Where the three books disagree is on what follows. One says withdraw, one says commit harder, one declines to say. I am sympathetic to the third.