Ever noticed how upgrading one thing means you have to upgrade another? There's a name for that — the Diderot Effect. (See also: Have Style, Not a Lifestyle)

We've just lived through an example of the phenomenon, because our apartment manager has just installed a bunch of upgrades in our apartment. It happened like this:

The very old kitchen faucet started leaking, requiring a new fixture. But the new fixture wouldn't fit into the hole in the old sink, so we needed a new sink. The new sink wouldn't fit into the hole in the old countertop, so we needed a new countertop.

Now, up to this point, the issue was just basic physics — things need to fit, or you've got problems. But then the issue shifted just a bit.

A new countertop on one side meant that we needed a new countertop on the other side as well, or they wouldn't match. (And the half-walls at the entrance to the kitchen were topped with islands that matched the old counters, so they needed to be upgraded as well.) And, with the new countertops, the kitchen cabinets started looking pretty shabby, so they needed to be refinished. And the kitchen walls needed a fresh coat of paint.

This is the dreaded Diderot Effect.

The Diderot Effect is named after the French writer Denis Diderot, who wrote a famous essay on how the gift of one very nice item had made his other things look shabby. In an amusing fashion, the essay traces out the series of steps by which he ended up having to upgrade everything he owned.

A whole lot of marketing is aimed at getting you to buy one nice thing — because the marketers know that having one nice thing will put you on the path to replacing many other items as well — things that are perfectly good, but that aren't as nice as your new thing.

It's an easy trap to fall into, and a terrible one.

Fortunately, the Diderot Effect is its own cure. While one nice thing makes your other stuff look shabby, when your stuff is all about the same, it produces a pleasant inertia that makes it easy to resist upgrades.

Add to this the concept of wabi sabi — which emphasizes such values as simplicity, functionality, authenticity, and modesty — and it becomes easy to resist the Diderot Effect.