Due to circumstances beyond my control—my wife had control of the remote!—I happened to catch this episode of The Oprah Winfrey Show a couple years ago.

Winfrey’s guests were the parents of a transgendered child. I’m not at all interested in criticizing or making light of what must be an incredibly complicated and trying situation for this couple. What caught my ear was Winfrey’s use of the term “evolved” to describe the couple’s decision to raise their biological boy as a girl.

This episode came back to me as President Obama’s “evolution” on the issue of same-sex marriage dominated the news cycle late last week. After hedging on the issue for some while, Obama announced he was in favor of legally recognizing the unions of gay couples. Not only had the president’s view on this issue “evolved”; we’re also to understand that this evolution is in some sense “complete.”

This is an abuse of the term “evolution.”

Evolution is not, or should not be, a synonym for progress—however one defines progress. Evolution does not have a linear endpoint. By its very nature, it can never be “complete.”

The evolution-equals-moral-progress fallacy might be thought of as the flip-side of the “survival of the fittest” connotation that the Derb identified here:

The misconception here, which also informs a lot of social-Darwinism twaddle, hinges on the word “fit.” We all know what it means in common usage, with connotations like healthy, strong, aggressive, etc. The phrase “survival of the fittest” therefore conjures up mental images of vigorous struggle, Nietzschean Blond Beasts lopping the heads off weaker specimens with broadaxes.

In biology, however, “fitness” is a term of art, a measure of how well an organism is adapted to its environment…

Take the humble butterfly, not really an emblem of violent struggle for supremacy. Yet butterflies have terrific fitness. They’ve been around for 60 million years! The tiger, by contrast, a much more struggly sort of organism, has been around less than two million years … and is on the verge of extinction. Butteflies are by no means the extreme. The real fitness world champions are deeply un-struggly organisms like the sea cucumber—400 million years and counting.

Another person’s moral preferences do not  “evolve” toward or “devolve” away from your own. If you mean to applaud Obama for his compassion or right-thinking, it’s rather an insult to use what is in essence a neutral term to classify his change of heart. Evolution doesn’t carry the baggage of virtue or vice. It simply is what it is.