As the results poured in on Tuesday night, a mini-narrative of triumph took hold among progressives: Finally, thank God, scientists have come to Washington. No fewer than 18 candidates with STEM backgrounds won their congressional races, according to FiveThirtyEight’s Maggie Koerth-Baker; and with the flipping of the House, the Committee on Science, Space and Technology will be chaired by a Democrat. For the first time in decades, this role goes to someone with actual scientific experience and training—former psychiatric nurse Eddie Bernice Johnson. Cue the banner headlines: “Science Returns to the House,” declared Mother Jones; “Science candidates prevail in US midterm elections,” said Nature.

It’s a nice idea that sending a wave of scientists and STEM professionals to Congress might help reverse the Trump administration’s tilt away from expertise and promote data-driven, fact-based approaches to public policy. Too bad it’s not really grounded in data or the facts. An egghead delegation won’t solve the problems in our nation’s capital, nor should we expect the presence of a few more physicists, engineers, and nurses to bring technical acumen or sanity into the House. That we’ve allowed ourselves to imagine otherwise only shows how blinkered we’ve become by a long-standing and overblown political narrative, that Democrats are fighting off a Republican war on science. A shaky subplot of this story is that progressives stand for science, scientists stand for progressivism, and victories for either group must overlap. That may not be true.

To argue otherwise, one must assume that scientists (or STEM professionals) are likely to share a certain set of skills and values, and that these skills and values would be good to have in government. It might be nice, for example, to see a knack for evaluating evidence among our representatives in Congress. Same goes for a tendency to accept the scientific consensus on anthropogenic global warming, and a general respect for scientific institutions and the value of basic research funding. But the degree to which those correlations hold depends on who’s included in the golden and heroic category of “scientist.” The biggest problem with the dream to rescue Washington with STEM is that it doesn’t carry any clear and useful definitions.

We don’t even have a steady way to talk about the baseline situation, in which the Congress—and its GOP contingent, in particular—is supposedly devoid of scientific expertise. Start with the case of former Fermilab physicist Rep. Bill Foster, a Democrat from Illinois who calls himself the “only Ph.D. scientist” in the Capitol. Poor science-minded Bill has made a habit of giving “lonely man in Congress” interviews, where he explains what’s it’s like to be out there on his own, fighting the good fight on behalf of science, a boffin floating in a sea of ignoramuses.

Is Foster really the only scientist in Congress? His colleague Rep. Jerry McNerney, D-Calif., holds a doctorate in mathematics (though he lacks Foster’s background in research). It might make sense to count up all the representatives with Ph.D.’s in scientific fields; in that case, the most recent Congress included three: Democrats Foster and McNerney, along with Republican Pennsylvania Rep. Tim Murphy. Murphy, who has a doctorate in clinical psychology and served on the faculty at the University of Pittsburgh, is certainly not the sort of science candidate whose electoral victory would have been ballyhooed in Mother Jones. Before he resigned last year over reports that he’d asked an extramarital sexual partner to have an abortion, Murphy was a reliable pro-life pro-guns voter in the House who opposed gay marriage and expressed reluctance to “declare climate theory a fact.”

In any case, it’s clear that no Democrat fighting against the war on science would argue that we should limit the definition of “science candidates” to those with Ph.D.s. Take 314 Action, a nonprofit formed in late 2016 with a goal to send more scientists and STEM professionals to Washington. That group formally endorsed 13 non-incumbent Democrats in this year’s general election, of whom eight were just elected into Congress. These included a dentist, a registered nurse, a pediatrician, a high-school chemistry teacher, and several engineers with Bachelor of Science degrees. None had Ph.D.s. And of course, we’ve already christened this moment “the return of science to the House” in part because Texas Rep. Eddie Bernice Johnson, the former RN, will soon chair the House Science Committee.

A shaky subplot of this story is that progressives stand for science, scientists stand for progressivism, and victories for either group must overlap. That may not be true.

But if we’ve settled on this broader definition of a “scientist,” then the present Republican-dominated Congress doesn’t look nearly as unscientific as it did before. Let’s consider just the doctors: There were about 16 physicians in the 115th Congress—of whom 14 were Republicans. If dentists also count as STEM professionals, as 314 Action suggests they do in its endorsements, then we should include another four representatives, all Republicans. Registered nurses are also in the club, of course, so let’s add another three (1 R, 2 D’s). And what about veterinarians: Aren’t they STEM professionals? If so, that’s three more (2 R’s, 1 D) for the total.

With that we’ve brought our number of science-minded members in the Congress that’s about to end up from one—lonely Bill Foster—to 29 , of whom three-quarters are Republicans. This does not include roughly a half-dozen engineers, another group of software executives, an ex-chemist, and an ex-microbiologist. Again, if we’re going by the standards set forth for our freshman class of science-legislators (comprising a chemistry teacher, an ocean engineer, etc.) then all of these incumbents should be counted as STEM professionals, too.

In practice it seems that when we talk about the surge of science candidates for Congress, we stretch and twist our definitions until they fit around whichever candidates we happen to like best. Case in point: Back in March, when the Washington Post asked the founder of 314 Action, Shaughnessy Naughton, why her group hadn’t backed any scientists or STEM professionals from the GOP, Naughton answered, “Bring me the unicorn.” (Naughton has used that formulation elsewhere, too, though as the Post pointed out, one of several such unicorns—Republican candidate and professional statistician Samuel Temple—was in fact running for the same seat as a Democratic tech entrepreneur endorsed by 314 Action.)

Or consider the jubilation over the change of leadership in the House Science Committee. The key fact here is that Eddie Bernice Johnson is replacing the arch-climate-skeptic and former journalist Lamar Smith as the chair. That’s something to celebrate. It’s also nice to know that science Ph.D.s Foster and McNerney are current members on the Democratic side, while not a single one of their GOP counterparts has a similar degree. (Little-known fact: There are currently more former car salesmen on the House Science Committee than Ph.D. scientists.) But what happens when you use the broader definition of a “scientist” favored by 314 Action and this week’s headlines on how “science candidates prevailed”? Now Johnson counts as a STEM professional, as she surely ought to, but so do about a dozen other members of the committee. We must acknowledge that, under this count, the GOP side has its own deep bench of scientific expertise: a dentist, three doctors, and three former engineers. That’s the same number of committee scientists or STEM professionals, overall, as you’d find among the Democrats.

My point is that for anyone invested in the idea of having scientists in Congress—as an end in itself, and a cause for celebration—these definitions and distinctions matter quite a bit. If you think it’s good to have science-minded legislators because they’re well-equipped to look at complicated evidence and arrive at logical conclusions, then keep in mind that not all STEM professionals have the same training. For example, you might be better off electing a meta-scientist, a statistician, a psychologist, or even an economist—all of whom may specialize in making sense of squirrelly, sprawling data sets—then going with, say, a bench biologist, a software developer, or an ocean engineer. And if you’re really concerned about “data-driven decision-making” then I’d suggest you steer clear of any practicing clinicians, who are often trained to follow standard guidelines rather than to sift through reams of evidence.

It also seems mistaken to assume that “science candidates” hold particular views on climate change or gun control or any other issue tied to scientific data. I’ve already mentioned Tim Murphy, the Ph.D. psychologist who happens to be a pro-guns, climate-change skeptic. It’s not hard to find other staunchly conservative Ph.D. scientists who have served in Congress recently. Take accredited physiologist Roscoe Bartlett, for example. He was pro-life and pro-guns; a scientist with an advanced degree who did not worry over climate change (but is quite worked up about peak oil).

If what we care about is data-driven, fact-based decision-making, then we should use that same approach to guide our choice of lawmakers.

Further, the push for scientists in Washington may be a project of the left today, but its politics are not exclusive. A few years ago, I wrote a profile of the oddball biochemist (and one-time shortlist-ee to be Trump’s national science adviser) Art Robinson. Here’s a man with views that most mainstream Democrats would find abhorrent and/or insane: He’s a fervent climate contrarian who believes that global warming will make the Earth more hospitable to humans; he’s an ultra-libertarian and a vaccine skeptic; and he argues that a little bit of radiation is likely good for everybody’s health. He’s also quite intelligent, and earnest, and has run for Congress several times on the theory that the country would be much better off if there were more empirical researchers in Washington. “I don’t think that scientists have any special skills at handling political decision-making,” he told me in 2017, “but they do have something to offer in government. Where science is involved in something that has to do with public policy, it’s good if the objective facts are available to the people making the decisions—and that that’s what I thought I might help with in Congress.”

Robinson’s motivation for seeking office, to improve policy debates in Washington by providing Congress with what he considers the most relevant, objective facts, might have sounded quite reasonable coming from any of the candidates endorsed by 314 Action, and whose election have been trumpeted this week as a victory for science. And isn’t that the point? If what we care about is data-driven, fact-based decision-making, then we should use that same approach to guide our choice of lawmakers. Don’t judge the freshman class in Congress by their bachelor’s degrees, or whether they’ve ever pulled a wisdom tooth. Look instead at what they’ve said they plan to do once they get to Washington.