The quiet arithmetic of saying yes

The cost of a yes is paid by someone who is not in the room.

Who pays for a yes

Agreeing to something costs nothing at the moment of agreeing. That is the whole problem. The yes is given by a present self who gets the social benefit immediately, and it is paid for by a future self who was not consulted and cannot object.

Three weeks later that future self arrives, discovers an evening is already spoken for, and is annoyed at somebody who is technically them. The mechanism is not weakness of character. It is that the costs and benefits land on different days, and the benefit lands first.

What a yes actually costs

More than the hours in it, which is why the diary is a poor guide. Four components, and most people count only the first.

• The time itself. The two hours, which is the part the calendar shows.
• The travel and the turnaround. Getting there, getting back, and the part of the surrounding time that is no longer usable for anything substantial because something is about to happen.
• The occupancy beforehand. A commitment on Thursday takes a small amount of Tuesday and Wednesday, because it sits in the background of planning.
• The displacement. Whatever the slot would otherwise have held, which is invisible precisely because it was never scheduled. The reading, the walk, the evening with nothing in it. These lose every contest with a specific request from a real person, which is why weeks fill with other people's priorities without anybody choosing that.

A way to cost one before giving it

Two questions, both answerable in about twenty seconds, and the second is the one that works.

First: would I accept this if it were next Tuesday? Distance is what makes a yes cheap, so collapsing the distance restores the real price. Most things agreed to for six weeks away would be refused for the day after tomorrow, and that gap is the size of the error.

Second: what am I taking this from? Not in general. Name the specific thing that will not happen. "I am taking this from the one evening I had free" is a decision. "I can probably fit it in" is not, and is how a month disappears.

Saying no without a reason

The sentence people are missing is short: "I can't, but thank you for asking." No reason, no alternative date offered reflexively, no apology beyond the ordinary.

Reasons invite negotiation, because a reason can be solved. Offering an alternative date in the same breath turns a no into a postponement, which is how the thing you did not want ends up in the diary a fortnight later.

This is easier in writing than in person, and easier after a pause than immediately. "Let me check and come back to you" is an entirely honest sentence that buys the twenty seconds the two questions need.

Where this advice stops

Obligation is real, and a framework for declining things is not a licence to decline responsibility. Some yeses are not optional and should not be costed: the family one, the one where somebody genuinely needs you, the one that is the job.

The arithmetic is for the large middle category of things that are merely nice, merely flattering to be asked about, or merely easier to accept than to decline. That category is where almost all the loss is.