This week, amid so much discouraging news of irredentist militias and unrepentant neocons, there was a small bit of news that might cheer people up, at least a little: Pluto, it seems, may be accepted back into the club of planets. It got kicked out, you will recall, eight years ago, when the I.A.U.—the International Astronomical Union, which exists to hold elections on these things—voted it out. It was too remote, too lonely, and generally too slovenly in its behavior to count as a planet. It even—lovely, incriminating phrase—failed to “clear the neighborhood around its orbit.” (And there seemed to be other even larger similar objects out beyond it.) It was demoted to a “dwarf planet,” and became a mere “Trans-Neptunian object.”
Now, though, Pluto has been discovered to have several moons, in regular orbit around it. It was already known to have three when it was de-listed, but the Hubble Space Telescope has since found two more. “Many Moons” was the title of James Thurber’s finest fable, and actually having many moons, apparently, helps make you a planet in the eyes of people on other ones, as having children was once said to make you an adult. One’s planetary distinction is redeemed, by this measure, by the clear presence of the orbit of the littler ones around you. And it could be a vindication for Pluto-lovers, too, a group who turn out to be more numerous than seems quite plausible. As you discover sifting through astronomical chat groups, the original decision to kick Pluto out of the planetary club was met with hysterical resistance, not to say resentment. Indeed, the state of Illinois decided, on its own, in 2009, to reinstate Pluto as a planet—making Pluto a planet when seen from Wrigley Field, merely a sub-Neptunian object across the way in Gary.
Some of the indignation on behalf of Pluto was, as so much indignation is these days, launched in the name of democracy. Apparently, only a small fraction of the I.A.U.’s members were there when the vote that booted Pluto was taken—one imagines it as a kind of Ted Knight-in-“Caddyshack”-style conspiracy of snobs, with poor Pluto in the Rodney Dangerfield part. No respect at all. But more of it seemed purely affective, astronomically tribal. Plutonic nationalism can be found everywhere. There are pro-Pluto Web pages, pro-Pluto books, pro-Pluto pressure groups. They contain, and generate, heated argument and loud accusation. (One anti-Pluto activist produced this perfect sentence: “We’ve heard this emotional story of planetary bullying over and over, so I won’t go over the details again.”)
The existence of the pro-Pluto party, on the verge of triumph at last, does seem to underline the rest of the week’s news, italicizing the perpetual human ability to take passionate sides in conflicts where the side-takers’ interests seem extremely remote. This is a general truth, reaffirmed again and again in modern history. Theorists of self-interest are always overwhelmed, in making predictions about human behavior, by theorists of irrational attachment—nationalism and clannism, no matter how destructive, have a way of trumping not just egalitarian fantasies but apparent economic interest, and this seems to be true right out to the edge of the solar system. Who cares whether we call it a planet or not? But people do. Picking sides, and planets, is what people do. (Illinois, it turned out, took the trouble to vote Pluto back in simply because the guy who first spotted it out there came from Illinois.) Those who imagine that picking sides is the small thing, easily overcome by common interests or even common sense, are generally, on this planet and every other, proved tragically, catastrophically wrong.
Whatever Pluto is, after all, it is, and the question of its classification, its taxonomic place, seems secondary to our understanding of why it’s a weird spot in the solar system. Science doesn’t only or even primarily ask “What is?” questions; it asks “How come?” questions. Not “What is gravity?” but “How come apples fall down instead of up?” What is man? Well, there is no answer, because he is not an essence but a long story, with lots of damn-close-to-a-man, sort-of-a-man, just-about-as-good-as-a-man, might-as-well-call-it-a-man, before we get to man—and we’re altering, too, even as we argue. The question of whether Pluto is or is not a planet is interesting only because it is, so to speak, the popular residue of an ever more interesting argument. It is really a shorthand way of asking, How was the solar system formed, and how many kinds and categories of objects can its history provide?
This kind of reasoning causes a panic because it seems that if you don’t have a definition, or have one that can be altered every few years, you must just have a guess. The resentment against science that is current now when it comes to subjects like climate change is not that scientists know too much; it is that they are not in a sufficient state of hysteria about not knowing for certain. They admit their fallibility, and still insist that they are worth listening to. This is the best guess we’ve got, they say, and the best guess we’ve got is the best guide to go on. (We saw this process under way in this morning’s Times, with a well-reported piece on the violent arguments back and forth about what exactly happened in the first trillionth of a second of the universe’s existence, and how you could know one way or another which story was true.)
And that, for the authority-anxious, is enraging, even though the practical advice is so clear. The odd thing is that, historically, acting on the best guess available has turned out to work out rather well, while relying on the sure thing known for certain since the beginning of time and revealed in a holy book has turned out to be a pretty poor strategy for finding out how this planet whirls among the stars while creating prosperous and peaceful places on it. Between anarchy and authority falls argument, and the arguments, even the seemingly remote ones, are always where the cool (if not truly, Plutonianly cold) stuff can be found.
Of course, a trendy, Pikettyish reason might also be deduced for the promised renaissance of the outermost planet. That reason is sinister, and simpler. What can it be, after all, but one more victory for the plutocracy?