1.6 Fundamental and Other Levels
The section is a discussion of the notion of "levels of reality". L&R begin with an interesting statement: "We seek an ontological model according to which science is unifiable, and which explains the basis for such unity as it can produce. This, we claim, is the point of naturalistic metaphysics." Now this is a stronger claim than L&R have been making so far. The point of naturalistic metaphysics, they said, is simply to unify scientific hypotheses. Up to now, there's been no concern about explaining the basis of unity.
L&R deny that the world is divided into "levels". Does the denial of "levels physicalism" entail emergentism? No: emergentism "holds that "higher" levels emerge indeterminably out of "lower" level ones and then causally feed back "downward"." But L&R deny that there are such levels. (Of course, perhaps their view, properly spelled out, does in fact entail emergentism. They have left the job of spelling their denial of levels to later chapters. But I agree that at this point we can't convinct them of inappropriate emergentism.)
1.7 Stances, Norms, and Doctrines
I found this to be one of the most interesting parts of the chapter. I'm afraid I don't have much to say about it myself, but I'll summarize L&R's views.
L&R begin this section with another argument against traditional metaphysics, this time drawn from Bas van Fraassen (2002). A notable feature of science is that it encompasses a variety of different goals: while scientists do aim for truth, this isn't their only aim; it's good enough for scientific work simply to be important, perhaps improving predictive accuracy, or practical know-how, or technological developments, etc. So it's not really a problem when a scientific theory is shown to be false. On the other hand, the only goal of metaphysics is true belief. Metaphysicians are not trying to improve social policy, or promote new research and development, or even to make predictions more accurate. They're concerned only with developing a correct picture of the world. A false metaphysical theory is therefore good for nothing, which is a problem given that almost all metaphysical theories are false (even defenders of traditional metaphysics must admit that almost all metaphysics is false, simply given the amount of disagreement among metaphysicians).
L&R then give an argument that philosophical positions should not be seen as doctrines, i.e. as collections of beliefs, but instead as stances, i.e. attitudes or commitments. The argument derives from van Fraassen and L&R's presentation of it is rather obscure. I will not follow their presentation, but instead use Ho (2007). Van Fraassen's argument begins as a dilemma for empiricism. Van Fraassen considers the following principle:
Principle Zero: For each philosophical position X there exists a statement X+ such that to have (or take) position X is to believe (or decide to believe) that X+.If we construe philosophical positions as sets of beliefs, this principle is surely true. All it says is that, in order to count as holding a certain position X, you must believe a certain statement that is defining of the position. (One objection might be that philosophical positions can be identified with clusters of beliefs, where no particular belief is necessary to count as an adherent of the position. It would be easy enough to reformulate Principle Zero to take account of this, though.) Applying this to empiricism, we have it that there exists a statement, call it E+, such that to be an empiricist is to believe E+.
What might E+ be? The central claim of empiricism is that there is no a priori knowledge. Every hypothesis must be subjected to testing against observation before it's accepted or rejected. Whatever exactly E+ turns out to be, then, it had better entail that no hypothesis can be ruled out a priori.
Here's the problem. Consider some non-empiricist hypothesis, M (suppose that M is some piece of speculative metaphysics). M denies or entails the denial of the claim that there is no a priori knowledge. Now, if we accept empiricism, we must accept that the dispute between E+ and M cannot be decided a priori - this is just the central claim of empiricism. The problem here is that E+ tells us that M must be wrong: given that we accept E+, we can immediately derive that M is false. M entails that there is a priori knowledge, but we accept E+, according to which there is no a priori knowledge, hence we must reject M. But now we're rejecting M a priori. E+ entails that we cannot rule out M a priori, and that we can rule out M a priori.
Since L&R's naturalism shares the empiricist commitment to the claim that all knowledge must be based on observation, experience, and experiment, it would appear that they face exactly the same dilemma. Van Fraassen's solution, with which L&R concur, is that philosophical positions must not be seen as collections of beliefs. There is no proposition E+. Principle Zero must be rejected. Instead, philosophical positions are stances, and while stances might include beliefs, they are based on attitudes, or commitments, or values, or ways of approaching the world. L&R quote van Fraassen approvingly: "Being or becoming an empiricist will ... be similar or analogous to conversion to a cause, a religion, an ideology, to capitalism or to socialism, to a worldview."
Van Fraassen considers two rival stances, the empiricist stance and the materialist stance, which are outlined as follows (these are not strict definitions; according to van Fraassen, stances are never finalized, and adopting a stance involves working out further details, discovering its implications, etc):
The empiricist stance: This stance has a positive and negative part. The positive part emphasizes anti-dogmatism, fallibilism, and a general support for the norms of science (perhaps viewing philosophy as on a spectrum with science), including the idea that no hypothesis should be ruled out a priori (this, as we saw, is the source of the dilemma that arises when treating empiricism as a doctrine). The negative part involves a resistance to demands for explanation concerning things for which no evidence can be provided (a question such as "what caused the universe to exist?" is likely to be dismissed, rather than answered, by the empiricist), and dissatisfaction for explanations that involve simply postulating things without evidence.
The materialist stance: This involves "a strong deference to the current content of science in matters of opinion about what there is." Materialist ontology is furnished by current science; materialism therefore tends to presuppose a scientific realism. The materialist stance also exhibits "an inclination ... to accept (approximate) completeness claims for science as constituted at any given time." There is nothing more in the world than what science allows. Whereas empiricism emphasizes science's anti-dogmatism and tolerance of novel theories, materialism emphasizes the more conservative elements of science: think of the very high standards, in terms of evidential support, coherence with the rest of science, etc, that any theory is required to meet before it's taken seriously.
While van Fraassen treats these as rivals, perhaps even the primary rivalry in the whole history of philosophy, L&R claim to adopt both stances. This is in line with their naturalistic approach, since both stances have a central role in actual science. They represent a significant tension at the heart of science: on the one hand, the encouragement of new ideas and novel hypotheses, on the other, the requirement that every hypothesis be subjected to ruthless criticism and empirical testing. This tension is an important part of what drives scientific progress, and L&R expect that metaphysics would be improved by incorporating it. The synthesis of the empirical and the material stances is achieved by their verification principle, the Principle of Naturalistic Closure. It's worth restating this principle:
First, no hypothesis that the approximately consensual current scientific practice declares to be beyond our ability to investigate should be taken seriously. Second, any metaphysical hypothesis that is to be taken seriously should have some identifiable bearing on the relationship between at least two relatively specific hypotheses that are either regarded as confirmed by institutionally bona fide current science or are regarded as motivated and in principle confirmable by such science.How does this help? As I noted, the empiricist stance emphasizes the liberal, more tolerant side of science; the materialist stance emphasizes its more conservative elements. By adopting a verificationism, the empiricist can "endorse tolerance, but within the limits of what is verifiable; for the materialist, verificationism is the way to keep order without resorting to the dogmatism of the ideological conservative." The synthesis of the empiricist and materialist stances is dubbed by L&R the scientistic stance. Why should we adopt the scientistic stance? L&R don't say much on this point, but I assume they would appeal to (1) the enormous success of science vs the poverty of other ways of attempting to develop knowledge, such as contemporary metaphysics; and (2) the fact that the scientistic stance synthesizes the empiricist and materialist stances, thus dissolving one of the central sources of disagreement in history of philosophy.
In the last paragraph of the chapter, L&R raise a potential difficulty for their view. Recall van Fraassen's criticism that the only virtue of metaphysics is that it's purported to be true. False metaphysics is useless metaphysics. But if L&R's metaphysics is based on science, it looks like they'll have to concede that it's probably false, since we have good reason to expect that current science will be overthrown by future developments. L&R's response to this worry is that the history of science doesn't support the pessimistic induction against the truth of current science. We have good reason to think that science progresses towards the truth, and that current scientific theories are mostly true. This is the topic of chapter 2.
I have two comments about this. First, an obvious defence of their metaphysics that L&R miss is that it has goals other than truth. In particular, it has the goal of unifying scientific hypotheses. Indeed on their view, unification is the whole point of metaphysics. If L&R's metaphysics is successful, it will help to unify scientific theories, and unification is worthwhile for reasons other than truth.
Second, their own defence of metaphysics is questionable even granting them the claim that we shouldn't expect current science to radically change. The problem is that they tie metaphysics to highly specific contemporary scientific hypotheses. This renders it far more vulnerable. Let's turn back to their discussion of the PNC, particularly their explanation of what it means for a scientific hypothesis to be specific. I didn't discuss this in the earlier post (largely due to my general lack of interest in articulating strict principles), but it's relevant here.
Metaphysics, L&R argue, must have a bearing on at least two specific scientific hypotheses. The point of requiring scientific hypotheses to be specific is to rule out hypotheses such as "all objects people can see without instruments are larger than atoms." We don't need to draw a strict line between the acceptable specific hypothesis and the unacceptable general ones - there's bound to be some vagueness - we just need a useful heuristic. L&R suggest that a specific hypothesis is the sort of hypothesis that one could "propose as the target of investigation in a grant proposal to a "serious" foundation or funding agency with non-zero prospects of success." (pg 33) The problem should now be obvious. If metaphysics is tied to hypotheses likely to secure funding, then much metaphysics is going to be tied to hypotheses that are likely to be wrong. Granting that current science is mostly true, much of that truth will reside in the older, well-established hypotheses that are less likely to subject to current investigation.
L&R themselves appear to be aware of this problem. They say it outright on page 35: "One consequence of naturalism that cannot be avoided is that if our current scientific image of the world changes much, as we suppose it will, then it will turn out that the best current metaphysics is substantially wrong." And if false metaphysics is useless metaphysics... well, so much for naturalistic metaphysics.
Well, that's all for chapter 1.
Ho, D. (2007) "Farewell to Empiricism", in Monton, B. (ed.) Images of Empiricism: Essays on Science and Stances, Oxford: Oxford University Press, pp. 319-333.
van Fraassen, B. (2002) The Empirical Stance, New Haven and London: Yale University Press.
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