Posts Tagged ‘scientific realism’

Was Montaigne right to be a skeptic?

For my senior thesis in college, I wrote on scientific realism—roughly, the view that our best current theories are approximately true. This was a mistake from which I still have not extricated myself, but every so often it pays dividends. Most recently, this came in reading Michel de Montaigne’s “Apology for Raymond Sebond”, the longest piece in his Essays. (In my edition, the Everyman’s Library edition of his Complete Works, the Apology comes to 170 pages.) Montaigne (1533-1592), in defending a general skepticism, offers an argument that is remarkably similar to an argument prevalent in the scientific realism literature today. I have my doubts as to the contemporary cogency of that argument. But in Montaigne’s day, I think it was devastating—more devastating, in fact, than Montaigne allows.

The argument in question now goes by the name pessimistic meta-induction (PMI). Its classic statement is in Larry Laudan’s “A Confutation of Convergent Realism” (available here). Laudan, in response to those philosophers who think that scientific realism is the only hypothesis that adequately explains the success of science, adduces a long list of theories that were once successful, but have since been rejected. Clearly, he claims, their success must not have been the result of their approximate truth, since they were not approximately true. Moreover, if rejection seems to be the fate of the successful theories of the past, on what grounds can we treat our current theories as immune to the same fate? What breaks the induction from the fate of past theories to that of current theories?

There are plenty of ways a realist might respond to this argument, but that is not my concern here, at least not yet. Rather, I am interested in the version of this argument given by Montaigne, and in the question whether he was right to make that argument. Here is what he writes:

The sky and the stars have been moving for three thousand years; everybody had so believed, until it occurred to Cleanthes of Samos, or (according to Theophrastus) to Nicetas of Syracuse, to maintain that it was the earth that moved, through the oblique circle of the Zodiac, turning about its axis; and in our day Copernicus has grounded this doctrine so well that he uses it very systematically for all astronomical deductions. What are we to get out of that, unless that we should not bother which of the two is so? And who knows whether a third opinion, a thousand years from now, will not overthrow the preceding two? (521)

This example is precisely the sort of example that the proponent of PMI offers: formerly, people believed one option, now they believe another—what is to say that in the future they will not believe some as yet unknown third? And, indeed, Montaigne had to wait only 300 years (and change), not a thousand, for Einstein to say that neither the earth nor the sun moves absolutely, but only relative to a reference frame—pick the right frame and one can easily say the sun moves while they earth stands still. My philosophy of physics friends tell me that Einsteinian relativity does not yet sit comfortably with quantum mechanics—is a fourth option around the corner? But I am getting ahead of myself, am moving too much into the present.

For what I really want to know is whether Montaigne, in the 1580s, was right to be a skeptic, and whether this argument offered persuasive grounds. I believe he was. Here is Montaigne’s practical proposal that results from this argument:

Thus when some new doctrine is offered to us, we have great occasion to distrust it, and to consider that before it was produced its opposite was in vogue; and, as it was overthrown by this one, there may arise in the future a third invention that will likewise smash the second. (521)

There is something of an obvious response to this advice, and it is one way that I am tempted to respond to PMI: all of this talk of the past is idle, what matters is whether we have good reason now. If the reasons offered in favor of some view are sufficiently good, should we not believe it? What does it matter that the reasons offered for past views were not good? If we have good reason to believe the view on offer, then we have good reason to think there will not arise a third invention.

This problem arises for Montaigne in part because he does not, or at least not here (he does elsewhere in the essay), consider the reasons given in favor of the theory. Rather, we are simply offered the theory, and since people have been offering false theories for so long, we should not expect any different of the new.  This seems to be too superficial, to eschew the use of one’s own reason to assess the reasons given. In fact I don’t think Montaigne overlooks this (he says elsewhere that we should not accept any hypothesis unless reason places it above its rivals), but the objection still requires a response.

The response Montaigne can give is, I think, this. The reasons we have been offered in the past led only to confusion and instability, and the reasons we are given now, while different in content, are not different in kind. That is, you are offering the same sorts of reasons today as were offered us in the past. Even if your reasons are better than those of the past, our history of failure tells us that we are highly fallible reasoners—else we would never have been taken in by those old views with their poor reasons. So, grant that your reasons appear better—what confidence can that give me that they actually are better? What possible reason could I have to think that you are or I am or anyone else is a competent judge?

So long as the reasons used to support our views remains of the same kind, Montaigne’s argument is cogent and powerful. He was right to be a skeptic. Of course, one can argue that, with what is called the scientific revolution, things changed. We started offering new sorts of reasons, and this eliminated the instability, such that now we can be realists about our best current theories. Laudan’s PMI aims precisely to undermine this optimism, to show that instability has not diminished since the 16th century. Perhaps he is right, perhaps not. That is a live debate. But as far as Montaigne goes, I do think that skepticism was the right position for him to take, for he had an argument that could take on all comers.



I forgot, in my initial post, to explain why Montaigne’s skeptical argument is more devastating than he allows. The reason for this is that it applies equally to religion, a possibility that Montaigne does not explore. The closest he comes is in the following passage:

O God, what an obligation do we not have to the benignity of our sovereign creator for having freed our belief from the folly of those vagabond and arbitrary devotions, and having based it on the eternal foundation of his holy word. (531)

Montaigne has all the material for a skeptical argument of the same sort as before: look at how many “vagabond and arbitrary” devotions humanity has subjected itself to, and how many were believed to have an “eternal foundation”—why should Christianity be any different. But Montaigne, in characteristic fashion, places his Christianity above doubt: he applies his doubt relentlessly to the earthly, but not to the eternal. There is no reasoned justification of this limitation of the power of his argument. Hence it is more devastating than Montaigne allows. It is tempting to wonder whether Montaigne did not know this, and was simply prudent in not challenging the church, but that is pure speculation, and may be combatted even without invoking powerful skeptical tools.


Two metaphors in Coleridge’s “Theory of Life”

2013/10/17 1 comment

UPDATE: For reasons that baffle me, this post has been cited as a source in a wikipedia article. If you were sent here from that, know that I am not at all an expert, merely an interested reader. I would not, if I were you, trust anything I say here.


My seminar on the boundary between humans and animals continues on to Samuel Taylor Coleridge, philosopher and poet, author of the long essay “Hints Towards the Formation of a More Comprehensive Theory of Life”. Here I want to explore two metaphors about the process of science as they arise in this essay. The essay may be read here, and page references are to that file.

Coleridge, in the “Theory of Life”, offers two quite different and quite interesting metaphors about the scientific process. The first metaphor, located in the essay’s first paragraph, is a call to rigor:

The positions of science must be tried in the jeweller’s scales, not like the mixed commodities of the market, on the weigh-bridge of common opinion and vulgar usage. (21)

The jeweler’s scales here represent accuracy and precision, as opposed to the much blunter tools of common opinion and vulgar usage. A further undercurrent of the metaphor is its relationship to honesty: accuracy and precision in this context are not purely descriptive virtues, but rather are connected to the discovery of the true value of the jewel. On the market, by contrast, the confusion created by common opinion and vulgar usage allows for swindling and deception. The essay begins by describing Coleridge’s opponents: those who have earlier attempted to define life, but have done so in a way more reminiscent of the market than the jeweler’s scales. The first metaphor, then, is not just a call to rigor; it is a reproach.

The second metaphor comes much later, and has quite a different tenor. It arises in the course of a friendly critique of John Abernethy’s theory of life:

In Mr. Abernethy’s Lecture on the Theory of Life, it is impossible not to see a presentiment of a great truth. He has, if I may so express myself, caught it in the breeze: and we seem to hear the first glad opening and shout with which he springs forward to the pursuit. But it is equally evident that the prey has not been followed through its doublings and windings, or driven out from its brakes and covers into full and open view. (65)

This is a much richer metaphor than the first. In the first, accuracy is achieved by the use of a precise instrument that measures the relevant quantity exactly. But what is to be measured is given: Coleridge says nothing of the extraction of the jewel. Here, by contrast, finding the truth is not a matter of calm measurement. It is a matter of a strategic and perhaps even dangerous pursuit against a worthy adversary. And, while Coleridge thinks Abernethy has failed in his pursuit, this failure is nothing like that of his earlier targets, who have failed even to rise above the discourse of the marketplace.

Why this difference in metaphors? The difference in tone may be attributed to Coleridge’s differing levels of respect for his targets. But what about the difference in content, between the hunt and the jeweler’s scales? What I want to suggest is that this difference in content is crucially related to Coleridge’s views about the aims of science and the status of scientific theories, and cannot be understood in isolation from them.

Sprinkled throughout the essay are various anti-realist remarks about quantitative scientific theorizing, sometimes at an abstract level and sometimes connected to particular theories. Thus, early in the essay, Coleridge remarks on the theory of “the French chemists” that it remains the dominant theory because of “the absence of a rival sufficiently popular to fill the throne in its stead” and not from “the continuance of an implicit belief in its stability” (23). This is a straightforwardly anti-realist attitude toward the theory: it is simply waiting to be replaced by a successor. Coleridge later generalizes the point: “For the full applicability of an abstract science ceases, the moment reality begins” (51), which receives an extensive footnote that begins by noting that abstractions are the “only subject of all abstract sciences.”

We can understand this view in light of Coleridge’s argument that everything that is, is Life. This argument itself is worthy of detailed consideration, but here I note only Coleridge’s comments about quantity and quality.

Our reason convinces us that the quantities of things, taken abstractedly as quantity, exist only in the relations they bear to the percipient; in plainer words, they exist only in our minds, ut quorum esse est percipi. For if the definite quantities have a ground, and therefore a reality, in the external world, and independent of the mind that perceives them, this ground is ipso facto a quality… (38-39)

Quantity, for Coleridge, is inherently mind-dependent, whereas external reality is qualitative. Quantity is nothing more than a human abstraction from this qualitative reality. The quantitative sciences, then, are properly considered with an anti-realist attitude—unless they are grounded in some qualitative reality.

Now it is worthwhile to recall that the first metaphor arises precisely in the context of an anti-realist argument about existing theories of life: these theories are to be rejected as insufficiently precise and rigorous. They do not pass the test of the jeweler’s scales; they belong in the marketplace. Indeed, Coleridge explicitly says that may be “sufficient, perhaps, for the purpose of ordinary discrimination, but far too indeterminate and diffluent to be taken unexamined by the philosophic inquirer” (21). But now consider the metaphor again. The jeweler’s scales are precisely a quantitative instrument—and so the jeweler’s measurements are inherently mind-dependent abstractions.

Coleridge, however, wants to claim for his theory more than the sort of anti-realist success of the abstract sciences. Why, then, a metaphor that, by his criteria, only points toward the quantitative sciences? Some light is shed on this by the presence of a frequent bugbear in Coleridge’s essay: the materialist. Coleridge on numerous occasions points out the impossibility of a materialist account of Life—that is why Coleridge’s vitalist alternative is needed. (Note that Coleridge is a strange sort of vitalist in that his vitalism unifies the organic and physical sciences rather than serving as a basis for their disunity.) Nevertheless, Coleridge does not deny the genuine scientific successes of materialistic theories. It is merely that these successes are quantitative and not qualitative—and so deserving of an anti-realist attitude.

Here the second metaphor comes in. No longer are we in the back room of the jewelry shop. We are out in the field, hunting. The pursuit of truth is now mixed with sweat and blood. In an almost literal way, this metaphor puts flesh on the first. Moreover, it comes precisely in the context of a realist argument. While he critiques Abernethy, Coleridge is concerned to say that Abernethy nonetheless has the presentiment of a great truth. Unlike the jeweler, Abernethy is on the path to truth, and not mere abstraction. Coleridge, by using the hunt metaphor, can thus characterize his own view as being simply further down this path than Abernethy’s view, thereby securing a qualitative, realist basis for his theory of life.