There Is No Scientific Method | New York Times

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Photo: James Blachowicz

"Why are the results of science considered more reliable than those from poetry or philosophy?" summarizes James Blachowicz, professor emeritus of philosophy at Loyola University Chicago and the author of “Of Two Minds: The Nature of Inquiry” and “Essential Difference: Toward a Metaphysics of Emergence.” 

Kepler’s illustration to explain his discovery of the elliptical orbit of Mars, circa 1754.
Credit Universal History Archive/Getty Images   
   

In 1970, I had the chance to attend a lecture by Stephen Spender. He described in some detail the stages through which he would pass in crafting a poem. He jotted on a blackboard some lines of verse from successive drafts of one of his poems, asking whether these lines (a) expressed what he wanted to express and (b) did so in the desired form. He then amended the lines to bring them closer either to the meaning he wanted to communicate or to the poetic form of that communication.

I was immediately struck by the similarities between his editing process and those associated with scientific investigation and began to wonder whether there was such a thing as a scientific method. Maybe the method on which science relies exists wherever we find systematic investigation. In saying there is no scientific method, what I mean, more precisely, is that there is no distinctly scientific method.

There is meaning, which we can grasp and anchor in a short phrase, and then there is the expression of that meaning that accounts for it, whether in a literal explanation or in poetry or in some other way. Our knowledge separates into layers: Experience provides a base for a higher layer of more conceptual understanding. This is as true for poetry as for science.

Let’s look at an example that is a little less complex than poetry. Consider how Socrates guided his students to a definition – of justice or knowledge or courage.

When Socrates asked “What is justice?” there was never any doubt that his listeners knew what the word “justice” meant. This is confirmed by the fact that Socrates and his listeners could agree on examples of justice. Defining justice, on the other hand — that is, being able to explain what it was conceptually that all these examples had in common — was something else altogether.

Suppose you and I try to define courage. We would begin with the meaning that is familiar to both of us. This shared meaning will be used to check proposed definitions and provide typical examples of it. Commonly, we may not be able to explain what something is, but we know it when we see it.

So what do we mean by courage? Let’s try, “Courage is the ability to act in the face of great fear.” This is an attempt to articulate (define) what we mean by courage. What we do next is to compare the actual meaning of courage we both possess with the literal meaning of the expression “the ability to act in the face of great fear.”

In comparing this literal meaning with the actual meaning of courage in our minds, we come to realize that the literal meaning of our working definition won’t work because, for example, “to act in the face of great fear” could include tying one’s shoelace, yelling profanities, even running away.

So we must alter our definition to exclude these typically non-courageous actions. One way of doing this is to produce a definition such as, “Courage is the ability to act in the face of great fear, except for tying one’s shoelace, yelling profanities and running away.” This does produce a literal meaning closer to the actual meaning we want to express or define.

Yet we wouldn’t accept such a definition even if it itemized every possible exception. Why? Because, from a different point of view, this definition is inadequate: not because it fails to bring the meaning of the definition closer to the actual meaning of courage, but because all it does is try to save the original definition by tacking on ad hoc exceptions. That is, we reject it because it fails to be a good, well-formed definition. A good definition is simple and provides a principle that would exclude all possible exceptions without having to enumerate them one by one.

What do we do? We come up with a new definition that once again is simple (without adding exceptions). We could try, “Courage is the ability to act while confronting a great fear.” Adding “confronting” would seem to disqualify tying one’s shoelaces and even shouting profanities since one could shout profanities while running away.

Yet adding an ad hoc exception may sometimes be just what is called for. Suppose I define courage as “the ability to act while confronting a danger to oneself.” “Confronting” is retained, so this would (normally) exclude running away. Yet one could also act out of anger, so that courage may not be the principal trait exhibited. We could add the ad hoc hypothesis “except when motivated principally by anger.” This would be desirable in this case, for the phenomenon turned out to be composite — actions that may arise from separate causes (courage and anger).

It’s important to see that this process — like that whereby a poem is written — rests on two requirements that have to be met. A good definition or poem must be one (a) whose expressed meaning matches the actual meaning that was grasped in a pre-articulated way and (b) which satisfies some criterion of form (embodies an explanatory principle or satisfies poetic form).

Now compare this with a scientific example: Johannes Kepler’s discovery that the orbit of Mars is an ellipse.

In this case, the actual meaning of courage (what a definition is designed to define) corresponds with the actual observations that Kepler sought to explain — that is, the data regarding the orbit of Mars. In the case of definition, we compare the literal meaning of a proposed definition with the actual meaning we want to define. In Kepler’s case, he needed to compare the predicted observations from a proposed explanatory hypothesis with the actual observations he wanted to explain.

Early on, Kepler determined that the orbit of Mars was not a circle (the default perfect shape of the planetary spheres, an idea inherited from the Greeks). There is a very simple equation for a circle, but the first noncircular shape Kepler entertained as a replacement was an oval. Despite our use of the word “oval” as sometimes synonymous with ellipse, Kepler understood it as egg-shaped (in the asymmetrical chicken-egg way). Maybe he thought the orbit had to be lopsided (rather than symmetrical) because he knew the Sun was not at the center of the oval. Unfortunately, there is no simple equation for such an oval (although there is one for an ellipse).

When a scientist tests a hypothesis and finds that its predictions do not quite match available observations, there is always the option of forcing the hypothesis to fit the data. One can resort to curve-fitting, in which a hypothesis is patched together from different independent pieces, each piece more or less fitting a different part of the data. A tailor for whom fit is everything and style is nothing can make me a suit that will fit like a glove — but as a patchwork with odd random seams everywhere, it will also not look very much like a suit.

The lesson is that it is not just the observed facts that drive a scientist’s theorizing. A scientist would, presumably, no more be caught in a patchwork hypothesis than in a patchwork suit. Science education, however, has persistently relied more on empirical fit as its trump card, perhaps partly to separate science from those dangerous seat-of-the-pants theorizings (including philosophy) that pretend to find their way apart from such evidence.

Kepler could have hammered out a patchwork equation that would have represented the oval orbit of Mars. It would have fit the facts better than the earlier circle hypothesis. But it would have failed to meet the second criterion that all such explanation requires: that it be simple, with a single explanatory principle devoid of tacked-on ad hoc exceptions, analogous to the case of courage as acting in the face of great fear, except for running away, tying one’s shoelace and yelling profanities.

Yet in science, just as in defining a concept like courage, ad hoc exceptions are sometimes exactly what are needed. While Galileo’s law prescribes that the trajectory of a projectile like a cannonball follows a parabolic path, the true path deviates from a parabola, mostly because of air resistance. That is, a second, separate causal element must be accounted for. And so we add the ad hoc exception “except when resisted by air.”

This is enough. There is much more to a theory of inquiry, of course, that could cover forms as disparate as poetry and science.

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Source: New York Times