As a science journalist, I’ve been to countless science conferences over the years where I’d hear about the latest discoveries or a plug for a new telescope or particle accelerator destined to yield fresh insights into the workings of nature. But last week I found myself in a small but elegant auditorium at Dartmouth College for a different kind of meeting. Scientists and philosophers had gathered not to celebrate research accomplishments but to argue that science itself is inadequate. As successful as it has undeniably been, they say it cannot provide all the answers we seek.
Now, make no mistake—they admit there is a certain kind of science that works incredibly well, when a little portion of the universe is cordoned off for study, with the scientist positioned outside of the carefully defined region under investigation. Galileo is usually credited with this extraordinary intellectual breakthrough, one that is often said to have paved the way for modern science. His observations of a swinging pendulum, and of balls rolling down inclined planes, are classic examples.
But what happens when we cannot draw a clear line between the observer and the observed? This, according to Dartmouth physicist Marcelo Gleiser and some of his colleagues, is a serious problem. And because these cases concern some of the most important unanswered questions in physics, they potentially undermine the idea that science can explain “everything.” Gleiser laid out this argument earlier this year in a provocative essay in Aeon, co-authored with astrophysicist Adam Frank of the University of Rochester and philosopher Evan Thompson of the University of British Columbia; and it was the focus of the two-day workshop that Gleiser organized, titled “The Blind Spot: Experience, Science, and the Search for ‘Truth’,” held at Dartmouth in Hanover, New Hampshire, on April 22 and 23. “Everything we do in science is conditioned by the way we look at the world,” Gleiser says. “And the way we look at the world is necessarily limited.”
Gleiser, Frank, and Thompson highlight three particular stumbling blocks: cosmology (we cannot view the universe from the “outside”); consciousness (a phenomenon we experience only from within); and what they call “the nature of matter”—roughly, the idea that quantum mechanics appears to involve the act of observation in a way that is not clearly understood.
Consequently, they say, we must admit that there are some mysteries science may never be able to solve. For instance, we may never find a “Theory of Everything” to explain the entire universe. This view contrasts sharply with the ideal that Nobel laureate physicist Sheldon Glashow expressed in the 1990s: “We believe that the world is knowable: that there are simple rules governing the behavior of matter and the evolution of the universe. We affirm that there are eternal, objective, extra-historical, socially-neutral, external and universal truths. The assemblage of these truths is what we call science, and the proof of our assertion lies in the pudding of its success.”
What Gleiser and his colleagues are critiquing, he says, is “this notion of scientific triumphalism—the idea that, ‘Just give us enough time, and there are no problems that science cannot solve.’ We point out that that is in fact not true. Because there are many problems that we cannot solve.”
The debate comes down to the question: Is the world knowable through dispassionate scientific study, or hopelessly viewpoint-dependent and full of blind spots?
Philosophers, not surprisingly, have weighed in. One approach that tries to take the “blind spot” concerns seriously, while still giving credence to a real world that exists independently of us, is a relatively new philosophical stance known as “perspectival realism.” Perspectival realism is, in part, a response to the “science wars” of the 1990s— a series of challenges levied against science by historians, philosophers and sociologists, who argued that scientific discoveries are shaped by the cultures in which they take place. It accepts that there are limits to science but recognizes its spectacular success in explaining nature, says Michela Massimi, a philosopher at the University of Edinburgh who spoke at the Dartmouth workshop. “Perspectival realism, in brief, says we should believe that science tells us a true story about nature,” says Massimi. “But the key question is, how to tell that story within … the boundaries of instruments, technologies, theories and model-building that are the products of particular scientific communities at particular historical times, in particular social and cultural contexts.”
This idea reflects a common theme heard at the workshop—that although science works, it can never hope to reveal nature “as it really is”; it can never produce a “God’s eye view” of the world. Rather, we can only know the world as it appears from our perspective. To complicate matters, however, one vital aspect of that perspective—conscious experience—tends to be left out of our scientific description of the world. We know the world through our experience of it, yet science struggles to explain this very experience. “I don’t know how science can actually address this problem,” Gleiser says.
But another philosopher at the workshop, Jenann Ismael of Columbia University, cautioned that the very charge that science ignores the observer misunderstands how science works and what it strives to accomplish.
A map can serve as a useful metaphor, she says. As you wander around an unfamiliar city, a map with a dot marked “you are here” can be very helpful. But we do not expect the map we pick up at the tourist office to have such a dot on it. Why not? Because, Ismael explains, those maps are for everyone, not just someone located at a particular spot. And that is what science is: our best attempt to “map” the world, not for “someone” but for “anyone.”
Ultimately, few would argue with a call for humility in science—or in any field, for that matter. But not everyone believes that the “blind spot” is a real problem. Sabine Hossenfelder, a physicist at the Frankfurt Institute for Advanced Studies, expressed her skepticism in an e-mail to Adam Frank. Experience, she said, can be studied just like any other phenomenon. “You come up with useful models about it. That’s what science does. If you have a predictive model, you say it ‘explains’ it. I don’t see why there is anything about experience that science cannot (at least in principle) explain.”
As the workshop drew to a close, I thought back to something my taxi driver had said as he drove me into town from the airport two days earlier. “There’s one thing I know about science, and that’s that you can never be 100 percent certain about anything.” I think even Galileo would have agreed with that.