Many people think it’s unfair for some people to earn a lot more than others for jobs that look similar on the surface. Consider pro sports, where recently people learned that rising stars like Caitlin Clark, Cameron Brink, Angel Reese, and others earn a tiny fraction of what male NBA players make. President Biden didn’t miss the opportunity to comment. “Why do players in the WNBA earn so little when their counterparts in the NBA earn so much? They work just as hard, and it isn’t fair. There ought to be a law.”

For Forbes, Caroline Reid reports a gender wage gap in the production of Disney’s famously progressive new show, The Acolyte.

Alas, it’s hardly clear people are underpaid, given that the WNBA has always been a money-loser rather than a money-maker (though the unprecedented attention on the WNBA means that might change), and The Acolyte has not been especially well-received by the Star Wars fandom.

Just because you have worked hard does not mean you have created value. Here’s an example to illustrate.

I recently decided to get back into collecting trading cards, toys, and other memorabilia. I’m selling a lot of it on eBay to learn more about online commerce—what better way to study transaction costs than to transact?—maybe breaking even with periodic great finds offsetting what I’m spending on stuff I just want to have (like a vintage Birmingham Steeldogs hat), and collecting fresh examples for the classroom.

One recent exercise illustrates why the labor theory of value is wrong. It can be summarized with a quote I’ve heard attributed to former Alabama football coach Gene Stallings (but sadly can’t verify): “Let’s not confuse effort with achievement.” Just because you worked hard at something doesn’t mean you have produced anything worthwhile.

That’s what happened when I opened 180 packs of 1990 Donruss baseball cards—about 3000 cards—and tried to assemble a complete set of about 750 cards, plus all the pieces to the Carl Yastrzemski puzzle that accompanied the set. Sorting the cards was fun and easy to do while watching TV or doing something equally brainless. By the time I was finished, I was about three cards short of the complete set.

So I ordered more.

Another thirty-six packs later, I had a complete set. It was the first time I’d assembled a set by hand. It took a while, but it was strangely satisfying.

So what is the set worth? I don’t think I will ever be used to the fact that as a highly educated middle-aged professional, my time is worth quite a lot more than it was when I was a preteen for whom there was no greater joy than buying a pack of baseball cards with fifty cents I had somehow scraped together. Would the set I assembled recently be worth more than the set I might have assembled 34 years ago, had I been willing and able to spend the kind of money that would have been necessary?

No. eBay says it’s worth maybe $20, and the time and energy I poured into it is irrelevant. I remember reading years ago someone speculating that Wayne Gretzky’s T206 Honus Wagner card might sell for $1 million, in part because the buyer would want the notoriety of having bought the world’s most valuable sports collectible from history’s greatest hockey player (the Great One ultimately sold it for a mere $500,000). I have yet to pay extra for anything on eBay because of who was selling it, nor have I ever asked how hard someone worked to find what I was bidding on. I’ve only asked, “is this the best price I can get?”

Labor is not, in itself, a source of value. Labor is expended in the pursuit of value, and the market process’s competing bids and offers convert people’s individual, subjective assessments into intelligible data called prices. Altogether, these create valuable signals called profits and losses, and the economic losses I’m incurring to assemble sets of borderline-worthless baseball cards from my childhood are the entire world coming together and screaming with one voice, “we hope you’re enjoying yourself, because in our estimation, you’re wasting your time.”

I am, thank you very much. And what better way to spend one’s time than to turn a hobby into an economics lesson?