Wednesday, March 19, 2014

Neil DeGrasse Tyson Is Wrong

Neil DeGrasse Tyson
Periodically, back in my teaching days, I’d perform a simple demonstration: I’d take a piece of chalk, hold it about head-height, and ask my students to speculate what would happen if I let it go. Naturally, everybody knew that it would fall. So I’d ask: “Who would like to write a paper about that?” No takers. Unsurprisingly. Then I’d ask: “Now who’d like to write a paper about why this chalk would fall?”

Sometimes I’d get takers right away. Often, though, my students would require some prompting. When I’d ask them what Newton said about how gravity works, what current science declares about gravity, or about gravity’s place in the still-hypothetical Grand Unification Theory, they’d realize how little they understand about something so obvious and comprehensible as, well, gravity. Such a fundamental force remains poorly understood by even our brightest minds.

I greatly admire American astrophysicist and media personality Neil DeGrasse Tyson. Unlike my college science instructors, Tyson is affable and telegenic, a master communicator who makes abstruse scientific concepts comprehensible to mass audiences. That’s why it worries me, in his current media tour promoting his reboot of Carl Sagan’s classic TV series Cosmos, that Tyson tells interviewers science is beyond debate. Because that’s just not true.

Let me define my point. Like Tyson, I don’t believe CNN and other media should permit “flat earthers” and seven-day creationists to present their anti-empirical positions as essentially equal to science. Any scientific position must rely on demonstrable evidence and, religious as I am, I deny that citing Genesis constitutes evidence. Ken Ham and his various cohorts who willfully deny confirmable evidence are, to pinch some technical terminology, nutcakes.

That said, while we can clearly spot what isn’t science, we have a harder time assessing what science actually is. Isaac Newton believed science relied upon experiment. The apocryphal story of his apple shows what that means: he observed a phenomenon, described a mechanism that explained that phenomenon, then devised experiments to test that mechanism. Because the mechanism accurately predicted experimental outcomes, he considered the mechanism proven.

Richard Feynman
When Tyson speaks of experiments and their results, he’s describing the Newtonian process. But he overlooks something important: the concept of gravity made Newton squeamish. What seems obvious to us now, because we’ve grown up with the idea, was so controversial that even its own inventor conceded that he’d found a sketchy preliminary conclusion, and he or somebody would have to devise a better, more seamless explanation for a strange and inexplicable phenomenon.

Thinkers like Leonardo and Galileo have bolstered Newton’s precepts about experiment. The (fictional) tale of Galileo dropping different-sized balls off the Leaning Tower of Pisa demonstrates this principle. But not everyone agrees. Albert Einstein had no patience for experiment. He believed higher math accurately described the universe, so he ran equations and, if the math held, he believed his principles proven. Demonstration was mere gravy for the plebs.

This is no small difference. Physics has made great leaps in recent decades, and Tyson derives the physical cosmology he describes on TV from current physics. But concepts like string theory and supersymmetry remain hotly debated in scientific circles because we only have math to go on, and while multiple equations prove sound and self-sufficient, they’re mutually contradictory. The theories hold up internally, but they can’t all be right.

And none has accurately predicted any experimental outcomes in thirty years.

Is science, then, the product when we test hypotheses and get desirable outcomes? Or is it the math that predicts the outcomes? And how do we reconcile irreconcilable outcomes? I contend that it is these debates, and not obvious physical facts, that constitute science. My students have no interest in writing about something obviously true. If I drop the chalk, it will fall. But as soon as I show them why that outcome is deeply controversial, they become interested.

Rhetorician Gerald Graff writes that “uncontroversially true statements are by definition inarguable and therefore not worth making, at least not as an essay’s main thesis.” This echoes what physicist Richard Feynman wrote about why we perform science: because the outcomes are in doubt. Once we resolve the controversy, the science stops. Obviously true ideas, like gravity, may be foundations for future science, but they are not science themselves.

Surely a decorated scientist like Tyson recognizes the importance of controversy in scientific thinking. This doesn’t mean journalists should give alien theorist Harold Ickes or climate denier Noel Sheppard equal time. But trying to deny the importance of debate makes science something it is not. And the entire scientific premise contradicts what Tyson has said in recent high-profile interviews. Frankly, this makes me sad.

See Also:
The Perils of Unsanctioned Thought in School

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