There was a philosopher once who had no patience with geekish hype about information technology. This application, he wrote, would never make people smarter or better. In fact, it made them lazier and more flighty, and left their minds worse off: The technology worsened their memories and replaced understanding and wisdom with mere collections of facts. Tsk-tsk.

The writer was Plato and the tech in question was writing.

Keep that in mind when you hear that digital media are screwing up our brains, as the New York Times solemnly announced this week.

This isn't to say that Plato was mistaken. No doubt Athenians' memories were much better when they couldn't take notes, and no doubt writing made possible a new kind of person—someone with book learning and no real grasp of what he was talking about—that didn't exist before. The Times is also correct that using digital media undoubtedly changes the brain.

So what? Everything changes the brain. It is constantly shape-shifting in response to experience, on every time scale from "entire lifetime" to "the last two hours." Consider, for example, the hippocampus, a region vital to forming memories, parts of which appear particularly important for remembering places you've been, and how to get there again. London cab drivers, who must master an enormous amount of geographical lore to get their licenses, have larger hippocampi than average.

On the vast scale, Michael Marmot and his colleagues found, for instance, that stressed-out underlings have worse memories (and worse overall health) than their bosses (one theory about why holds that the low-status workers pay a psychic price for having little control over their days). On the minute-by-minute level, consider this study at East Carolina University's Psychophysiology Lab, which found an immense (and positive) effect on mental function in people who had played videogames for all of 30 minutes.

It's not news, then, that digital media change brain and behavior. It would be news if they didn't. The important question is, instead: are these changes harmful to people, or to society as a whole? That's hard for a human being to answer, for two reasons.

One is that we're all inclined to confuse personal discomfort with global catastrophe. I didn't grow up with cell phones, for example, so I find it disconcerting when people check out of a face-to-face conversation in order to talk to someone who isn't physically there. But what feels rude to me strikes others as normal. It must be because there's something wrong with them! That's the most comforting possible explanation, which is why it's so attractive.

Naturally, I'll want confirmation—hard evidence that my self-flattering intuition is correct. Let's measure the harmful changes wrought by technology! But that leads to the second difficulty: Technology, by changing people, alters their definition of "harmful," "normal" and "desirable." By the time we're trying to decide what to do about IM-ing or MMORPG's, we aren't the same society as the one that invented them. Nicholas Carr can deplore "what the Internet is doing to our brains" for a few more years, but eventually, the doing will be done, and he will be gone. I am all for tracking the effects of the digital revolution. But could we please do it without the moral panic?