For reasons that are not entirely clear to me, Elon Musk decided to troll some socialists on Friday.

Those who proclaim themselves “socialists” are usually depressing, have no sense of humor & attended an expensive college. Fate loves irony. — Elon Musk (@elonmusk) June 15, 2018

He kept trolling over the weekend.

“No sense of humor” is certainly proving itself true. Good grief!

How many socialists does it take to screw in a lightbulb?

Answer: That’s not funny!! — Elon Musk (@elonmusk) June 16, 2018

By the way, I am actually a socialist. Just not the kind that shifts resources from most productive to least productive, pretending to do good, while actually causing harm. True socialism seeks greatest good for all. — Elon Musk (@elonmusk) June 16, 2018

There are, of course, much more important issues in the world right now than a billionaire’s Twitter taunts. Children are being torn from their parents at the border, and the Trump administration is gearing up to strip more naturalized Americans of their citizenship based on technicalities. Elon Musk’s dime-store political philosophizing at the expense of rose Twitter is not that important, even if he is an influential, powerful guy.

But I do want to take a moment to unpack this troll just a bit, because it is kind of amazing. While socialism is a somewhat fuzzy term these days, it’s generally understood to mean a political system where the government engages in a good deal of wealth redistribution. When Musk says, “True socialism seeks the greatest good for all” and that he does not support a redistribution of wealth to the “least productive,” it sounds a lot like he’s talking about Pareto efficiency, a theoretical state where absolutely nobody can get richer without somebody else becoming poorer. In a Pareto equilibrium, you could have a society that’s collectively as well-off as possible—that’s Musk’s “greatest good for all” line—even if the majority might be a lot better off with a bit of redistribution.

For a long while, economists tended to view Pareto efficiency as the end-all-be-all of policy design. This wasn’t entirely bad, since it tended to focus researchers on ideas that might lift all boats, or at least lift some without sinking others. But it also partly explained the profession’s free-market leanings, since, in theory at least, letting capitalism do its thing is a good way of maximizing total resources on paper, if not creating a just or livable society. Socialists, meanwhile, tend to care less about Pareto optimality and think more about how resources are distributed among people. Of course, I’m simplifying a bit here. Plenty of left-leaning but mainstream economists also care about distribution these days. Plenty of DSA members think we could potentially be a richer country overall with a different economic system. And, to get technical about it, there are Pareto-optimal models that allow for some redistribution. But historically, whether you cared about maxing out society’s wealth or making sure it was fairly divided has been a fundamental split between laissez-faire types and socialists. In other words, Musk more or less seems to be redefining socialism as capitalism. Way to flip the script Elon!