It is past all controversy that what costs dearest is, and ought to be, most valued.

What you paid for in effort, waiting or risk sits differently with you than what arrived easily. Part of that is fair, since the cost was real and it belongs to the thing’s history. Part of it is a trick of the mind, which defends its expenses. Both are worth knowing: the first tells you what to protect, the second when you are protecting a mistake.

Look at something you value largely because it was hard to get. Ask whether you would choose it again at today’s price. If not, the money and years are already spent, and keeping it will not bring them back.