Philosopher (and scientist, mathematician, logician, etc.) Charles Peirce, in a well-known 1877 essay, tried to defend the scientific method on pragmatic grounds alone, saying it’s the most successful way, given our peculiar status as rational animals, to cure doubt and fix belief. But if what I’ve been going on about is true—namely that science grates on human nature, and that relatively few people are motivated to doubt their beliefs in the first place—then Peirce can’t be right, and we’d have no independent reason to endorse the scientific method over and above other means of settling opinion. ‘It just works’ is a bad argument if it doesn’t work.

So where do we stand? Let’s say we hold to our analysis and decide that Peirce has missed the mark. Let’s say he’s wrong about human nature. Do we have to give up on science, then, and say it’s no better than alternative routes to belief? Is there really nothing that sets it apart? You can guess that my answer is ‘no’. But so too, I think, is Peirce’s—despite his superficially pragmatist narrative. Science is better than alternative routes to belief because the path it charts wends toward truth.

So say I. But I want to convince you that Peirce too, deep-down, regards science as truth-sensitive in this way—connected to objective reality—and that it is this fact which gives it its special potency in doing away with doubt. Peirce understands that we humans care about truth, and he thinks that science can deliver it best.

What makes me so sure? Start with this. On the way to explaining why science-based beliefs alone can withstand the seeping erosion of doubt, Peirce writes: ‘it is necessary that a method should be found by which our beliefs may be caused by nothing human, but by some external permanency—by something upon which our thinking has no effect’. What external permanency can he mean, if not a stable state of affairs—a real world—to which science has special access? Actually, shortly after the quote I’ve just given, Peirce spells out, and even seems to endorse, the keystone hypothesis of the scientific worldview: ‘There are real things, whose characters are entirely independent of our opinions about them; those realities affect our senses according to regular laws, and … we can ascertain by reasoning how things really are’. Finally, he writes that if ‘a man … wishes his opinions to coincide with [fact], [it will be] the prerogative of [science]’ to produce the desired effect. This appears to be scientific realism plain as day. How can Peirce defend such a view in the course of an otherwise insistent pragmatism?

To answer this, let’s give Peirce’s train of thought another look. Doubt, he says, arises from the irritating friction of two (or more) incompatible propositions. But then someone who doubts must believe that there is some one state of affairs against which the competing propositions could be decided—in other words, an external, objective reality. Now, we all doubt; so we must all believe in an external, objective reality. So we are all by nature realists. The scientific method—Peirce then suggests—is the sole contender that posits an external reality or objective truth, so it is the only one that can calm the friction of our doubt.

Let me be careful now. Peirce is not (strictly) saying that the central tenet of science—realism—is true. That would be decidedly un-pragmatic. Instead he is saying that it happens to be the case that we believe it to be true, and cannot help ourselves. That Peirce himself believes this along with the rest of us, and that this belief bolsters his commitment to science, I still have to show. But let’s pause here to consider in more detail Peirce’s reference to folk realism, in order to work out its role in his argument.

This is the claim. We are most of us naïve realists. That much is probably uncontroversial: a quick humanity-wide Gallup poll would certainly reveal an overwhelming bias toward belief in some version of external reality. But it’s a long way around the isthmus from this observation to Peirce’s main point, namely that science is the surest practical way to conquer doubt. After all, I may believe, along with just about everyone else, in the existence of an objective, mind-independent reality—without necessarily endorsing the scientific method for everyday belief-formation, or finding it particularly compelling in general. Expert disciples of the method of tenacity (see Part II), for instance, are very likely realists. They think that the world exists. They think that their own beliefs about the world are objectively true. And they think that the competing beliefs of other people are objectively false. So if what I’ve said in earlier posts is correct—namely that most people practice some form of this tenacious method—then Peirce would still be wrong to say that the scientific one triumphs on pragmatic grounds. To put it another way, since both the method of tenacity and the scientific method are compatible with everyday, man-on-the-street realism, belief in an external world is poor evidence for the exclusive power of science to relieve doubt.

Why, then, is Peirce so loyal to the scientific method? I think—if I may resort to something halfway between textual analysis and psychoanalytic speculation—that it’s because Peirce himself is a scientist. He is enamored with science, and thinks you should be too. ‘All the followers of science’, he writes, ‘are fully persuaded that [its methods] will give one certain solution to every question to which it can be applied’. 

Or consider that different minds may set out with the most antagonistic views, but the progress of investigation carries them by a force outside of themselves to one and the same conclusion. This activity of thought by which we are carried, not where we wish, but to a foreordained goal, is like the operation of destiny. No modification of the point of view taken, no selection of other facts for study, no natural bent of mind even, can enable a man to escape the predestinate opinion.

Here is a man in love. Peirce is expressing in hushed, adoring phrases that same reverence for science which I once knew myself (see Part I). But ‘most of us … are naturally more sanguine and hopeful than logic would justify’ and Peirce’s own optimism may be a case in point. His argument for the practical grounding and palliative effects of science seems to groan under the weight of so much counter-evidence: provincialism, tribalism, ideological indoctrination, and partisan hollering, just to start. The virtuous social impulse that he credits to our species’ inmost nature—that tendency to fundamentally doubt our own beliefs when we see that others think differently from us—if it ever was essential, may now be vestigial at best. And science, I’ve tried to show, is more bewildering than bewitching.

But Peirce could still be right in the long-run, for he tunes his optimism to the arc of infinity. ‘Our perversity’, he writes, ‘may indefinitely postpone the settlement of opinion; it might even conceivably cause an arbitrary proposition to be universally accepted as long as the human race should last. Yet even that would not change the nature of [a true] belief, which alone could be the result of investigation carried sufficiently far; and if, after the extinction of our race, another should arise with faculties and disposition for investigation, that true opinion must be the one which they would ultimately come to.’

This is realism. Even for Peirce, that is, some one truth exists. The world really is a certain way—whatever that way may be; and though it may take us an infinity to see it, it is out there nonetheless. Science, Peirce believes, is the only vehicle capable of making the trip (whether we choose to embark or not). So we must come to the following conclusion. For the father of pragmatism, the answer to our question about science and reality is yes. Science can—and can exclusively—tell us what is objectively true about our world.