We have a method July 12, 2011Posted by Ezra Resnick in Science.
Tags: Carl Sagan
Carl Sagan begins his essay “Wonder and Skepticism” (published the year before he died) by describing the feelings of hope and awe that inspired him to study science as a child, leading to the joy and excitement of his career as a scientist and a popularizer of science. Sagan realizes, however, that scientific thinking remains foreign to many people, and he warns of the dangers inherent in a scientifically illiterate society:
There’s another reason I think popularizing science is important, why I try to do it. It’s a foreboding I have — maybe ill-placed — of an America in my children’s generation, or my grandchildren’s generation, when all the manufacturing industries have slipped away to other countries; when we’re a service and information-processing economy; when awesome technological powers are in the hands of a very few, and no one representing the public interest even grasps the issues; when the people (by “the people” I mean the broad population in a democracy) have lost the ability to set their own agendas, or even to knowledgeably question those who do set the agendas; when there is no practice in questioning those in authority; when, clutching our crystals and religiously consulting our horoscopes, our critical faculties in steep decline, unable to distinguish between what’s true and what feels good, we slide, almost without noticing, into superstition and darkness…
We have a civilization based on science and technology, and we’ve cleverly arranged things so that almost nobody understands science and technology. That is as clear a prescription for disaster as you can imagine. While we might get away with this combustible mixture of ignorance and power for a while, sooner or later it’s going to blow up in our faces. The powers of modern technology are so formidable that it’s insufficient just to say, “Well, those in charge, I’m sure, are doing a good job.” This is a democracy, and for us to make sure that the powers of science and technology are used properly and prudently, we ourselves must understand science and technology. We must be involved in the decision-making process.
Why is science so amazingly successful? How does it achieve such uncanny accuracy and predictive powers, despite our human fallibility? Sagan explains that the key to the scientific method is its “built-in error-correcting mechanisms”: arguments from authority are worthless; claims must be demonstrated; criticism is desirable; disproving previously accepted ideas is laudable.
It all comes down to experiment.
Scientists do not trust what is intuitively obvious, because intuitively obvious gets you nowhere. That the Earth is flat was once obvious. I mean, really obvious; obvious! Go out in a flat field and take a look: Is it round or flat? Don’t listen to me; go prove it to yourself. That heavier bodies fall faster than light ones was once obvious. That blood-sucking leeches cure disease was once obvious. That some people are naturally and by divine right slaves was once obvious. That the Earth is at the center of the universe was once obvious. You’re skeptical? Go out, take a look: Stars rise in the east, set in the west; here we are, stationary (do you feel the Earth whirling?); we see them going around us. We are at the center; they go around us.
The truth may be puzzling. It may take some work to grapple with. It may be counterintuitive. It may contradict deeply held prejudices. It may not be consonant with what we desperately want to be true. But our preferences do not determine what’s true. We have a method, and that method helps us to reach not absolute truth, only asymptotic approaches to the truth — never there, just closer and closer, always finding vast new oceans of undiscovered possibilities. Cleverly designed experiments are the key.
To avoid sliding into the “superstition and darkness” that Sagan feared, we must teach children to be skeptical and critical — while also preserving their willingness to evaluate new ideas with an open mind.
Science involves a seemingly self-contradictory mix of attitudes: On the one hand it requires an almost complete openness to all ideas, no matter how bizarre and weird they sound, a propensity to wonder. As I walk along, my time slows down; I shrink in the direction of motion, and I get more massive. That’s crazy! On the scale of the very small, the molecule can be in this position, in that position, but it is prohibited from being in any intermediate position. That’s wild! But the first is a statement of special relativity, and the second is a consequence of quantum mechanics. Like it or not, that’s the way the world is. If you insist that it’s ridiculous, you will be forever closed to the major findings of science. But at the same time, science requires the most vigorous and uncompromising skepticism, because the vast majority of ideas are simply wrong, and the only way you can distinguish the right from the wrong, the wheat from the chaff, is by critical experiment and analysis.