We live in a world that is knowable, understandable, observable. A world that is completely mind-independent. It does not yield to our perceptions, our perceptions yield to it. And any theoretical conception conforms precisely to the reality of the natural world.
These are the claims of the scientific-realist.
These are the claims that allow us comfort, security, knowledge.
These claims are false.
In order to prove the falsity of such claims, I will rely on three premises: reality is mind-dependent; the criterion problem is inescapable; all scientific claims refer to paradigms, which refer to a mind-dependent reality and not to a mind-independent external world.
Idealism and the end of objectivity
Scientific claims are predicated on the assumption that there exists some verisimilitude between our perceptions and the external world. The direct realists contend that we have accurate and immediate access to the external world through our senses. Qualities such as extension, motion, color, and smell reside entirely in objects themselves and our senses infallibly relay this information. Direct realism is, however, an untenable position. Our senses deceive us (displacement, phantom limbs). Colors reside in the mind, as do sounds, smells, and temperature. But we must hold on to the idea that the external world is real and that we have some accurate conception of it, right?
In an effort to reconcile this problem, John Locke developed the notion of primary and secondary qualities. Primary qualities, such as size and shape, exist in the objects themselves exactly as we perceive them. Secondary qualities, such as color, taste, and sound, are sensations produced in the mind from the primary qualities. Matter vibrates at such and such a frequency, thereby producing a sensation in the mind via the senses, which is then in turn interpreted as the color green, the taste sour, or the warmth of a fire. Both primary and secondary qualities produce ideas in the mind, but Locke’s distinction is that the ideas produced by the primary qualities resemble the actual objects, while those produced by the secondary qualities do not. This distinction is important; it is, unfortunately for the indirect realist, arbitrary.
George Berkeley attacked Locke’s ideas and the notions of realist and indirect realism, arguing that both views were incoherent. Locke claimed that our ideas of primary qualities resembled the objects themselves. Berkeley responds that an idea can be nothing but an idea, it can only resemble itself. Therefore, it cannot resemble an object. It is a matter of the simple logic of identity: A=A. After all, if external things, or “originals” of which our ideas are mere copies, do exist, are they perceivable? If so, then we can only perceive them through our ideas of them and Berkeley has won his point. If they are not perceivable, then what sense would it make to say that a color is like something invisible; that something hard or soft is like something intangible; that sour is like something tasteless?
Locke’s resemblance theory appears to be in trouble, if not refuted outright, but what about his notions of primary and secondary qualities? Berkeley argues that the same reasoning which allows the distinction of primary and secondary qualities also prohibits such a claim. Firstly, it is impossible to separate these two qualities through abstraction. I cannot conceive of a square without it having some color, for instance. There is no good reason to assert that the shape of the square exists outside of the mind, while the color does not. Secondly, it is posited that heat and cold are properties of the mind. One pool of water can feel both hot and cold, depending on the relative dispositions of the bodies therein submerged. But why, Berkeley asks, should we not apply this same reasoning to figure and extension and motion? Do not certain objects appear to have certain shapes, sizes, speeds depending on the relative dispositions of the minds by which they are being perceived?
Berkeley’s fatal blow comes from a now-infamous thought experiment. The challenge is thus: conceive of one extended movable substance to exist otherwise than in a mind perceiving it. Surely, you say, I can imagine trees, books, a car, my bedroom existing without anyone there to perceive them. But are you not simply perceiving certain ideas of trees, books, cars, bedrooms, while simply removing the idea of anyone there to perceive them? In order to fully meet Berkeley’s challenge, it is necessary that you conceive of them existing unconceived or unthought of, which is a manifest contradiction.
These attacks on direct and indirect realism, even if they are not wholly convincing to the reader (and they are certainly counterintuitive), do cast serious doubt on the notion that we have reliable access to an external world beyond that of our own ideas. The arguments of Idealism show that it is at least possible that we live in a world that is completely mind-dependent, a world of sensations, images, sounds, tastes, objects, figures that exist solely in our heads. If this is true, then there are no more objective claims because there is no more objectivity. Mind-dependent reality is entirely subjective.
The criterion problem
We all know the scientific method. Observe a phenomenon, develop a hypothesis, and set up an experiment to confirm or deny said hypothesis. But what happens, as it often does, if more than one hypothesis provides a valid explanation? This is when scientists employ the Inference to Best Explanation method. Essentially, this means that one infers, from the premise that a given hypothesis would provide a “better” explanation for the evidence than would any other hypothesis, to the conclusion that the given hypothesis is true. It sounds nice, simple, logical. The question of whether or not it can be expected to yield any scientific knowledge preferable by the realists, is a matter of dispute.
This is where the Criterion Problem rears its ugly head. In order to judge that one theory furnishes a better explanation of some phenomenon than another, one must appeal to some criterion on the basis of which the judgment is made. Let’s say that a ubiquitous criterion is simplicity (think Occam’s Razor). Simplicity, then, justifies the choice of one hypothesis over another. But what criterion justifies the criterion of simplicity? We must appeal to another, antecedent criterion, X. I’m sure you can see what’s coming next. What criterion justifies criterion X? We find ourselves in an infinite regress. Perhaps somewhere towards the beginning of this long chain of criteria is the notion of direct or indirect realism, which we have already shown to be in serious trouble. Perhaps there is no solid, unassailable principle nestled somewhere in this ever-regressing line. Our foundation for knowledge seems precarious.
A system of paradigms
Given the problems of Idealism and the inescapable Criterion Problem, how do the sciences justify their explanations? They set up paradigms. Since the reality of the scientific worldview seems to be filled with logically inconsistent metaphysical theories and unjustifiable hypothesis, a system of paradigms functions so as to create the reality of scientific phenomenon, thereby allowing scientists to engage with this reality. The semantic content of the scientific lexicon, the terms and their meanings, but also the referents of those terms, are constrained, limited, encapsulated by paradigmatic boundaries. The idea of a paradigm-transcendent world which is investigated by scientists, and about which one might have knowledge, has no obvious cognitive content, logical consistency, or semblance of coherency. It is a fiction.
The science of the unknowable: a summation
The notion of any verisimilitude between scientific claims and reality is patently false. With Idealism, objectivity fails, as does any claim on observational truth. All science can do is make claims about what we assume to be the natural world. The problem is, there is simply no justification for these assumptions. The Criterion Problem is ineluctable. The laws and theories of the established paradigms only apply to those paradigms and not necessarily to anything which exists outside of them. In fact, it seems as if it is impossible to know of anything existing outside of a mind-dependent world. After all, how could we conceive of an unconceived thing? There is a vast divide, an irreconcilable disconnect, a chasm, a gulf, a void, an insuperable epistemological barrier separating us from certainty.
We place a great deal of emphasis on our ability to understand our world through scientific advances. We like to think that if we render the world meaningful and purposeful, then perhaps we could find some meaning and purpose. If we could subdue the chaos with logic and reason, then everything would be logical and reasonable. We forget that as we search for meaning, purpose, logic, and reason, we effectively create it. Order imposed on a system does not prove that a system imposes order. The structure of these statements is circular and self-contained. Much like our reality.