What the stand-in does

The third coffee helps. So does the biscuit. I'm not going to pretend they don't, because you can feel them helping and a book that argues with your own senses loses. What I want to show is what they help with and for how long, because that's where the habit lives.

At the flat hour you're heavy, dull, headachy and wanting something. Part of that is the natural afternoon dip, part of it is the dryness. The coffee addresses the dip. Caffeine lifts alertness for a while, and it lifts it regardless of what caused the low. The biscuit addresses the wanting, briefly, and gives you something to do with your hands and a small pleasure. Neither addresses the dryness at all. The coffee brings a cup of fluid with it, which is something, and the biscuit brings nothing.

So an hour later the lift has gone, the dryness is where it was, and you're back at the flat hour, wanting something, with the tin still there. This is my interpretation, not a finding, but I think the structure is clear. The stand-in relieves the symptom of a state and leaves the state in place, so the symptom comes back, so the stand-in is needed again. That's how a third coffee becomes a fourth, and a biscuit at two becomes one at four.

There's a fair objection. If you drank the water and skipped the coffee, you'd lose the lift, and the lift is real. Yes. You'd also lose the flat hour's dryness, which the coffee wasn't touching, and you'd keep your evening. Whether the lift is worth the evening is a question for the coffee book. For this one, the question is whether you want to keep needing the lift, and the answer to that is partly in a glass.

The glass first, in chapter 17, doesn't ban the stand-in. It puts a glass and ten minutes in front of it. If you still want the coffee after that, have it. Most afternoons, I'd expect you to want it less, because part of what it was standing in for has been dealt with.