Abstract
It is widely acknowledged that metaphysical assumptions, commitments and presuppositions play an important role in science. Yet according to the empiricist there is no place for metaphysics as traditionally understood in the scientific enterprise. In this paper I aim to take a first step towards reconciling these seemingly irreconcilable claims. In the first part of the paper I outline a conception of metaphysics and its relation to science that should be congenial to empiricists, motivated by van Fraassen’s work on ‘stances’. There has been a considerable about of recent work devoted to van Fraassen’s ‘stance’ view, but it has not on the whole been noticed that the view has the potential to motivate a general empiricist conception of the relation between science and metaphysics. In the second and third sections I discuss two examples from biology to illustrate this conception: metaphysical punctuationism, and its relation to and influence on the thesis of punctuated equilibrium; and dialectical biology as defended by Levins and Lewontin.
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Notes
It will be seen that the position I am exploring has some affinities with the view defended by Kant, on the positive role of reason, in the Appendix to the Transcendental Dialectic, from his Critique of Pure Reason (1965, 532-549).
Or indeed philosophers of science practicing what has been called the metaphysics of science.
van Fraassen is of course best known for defending the anti-realist position in the philosophy of science known as constructive empiricism (CE). This is the view that the aim of science is empirical adequacy rather than truth, and that the acceptance of a theory amounts to the belief that it is empirically adequate (van Fraassen 1980, 12).
Chakravartty (2010, 63) mentions CE, along with logical empiricism, as a perspective from which one may reject a role for metaphysics in science, given the epistemic attitude it promotes towards unobservables. According the CE, the positing of unobservable entities plays an important role in science only inasmuch as it assists scientists to develop empirically adequate theories, and CE recommends an attitude of agnosticism towards the question of the existence of these entities. But we have seen that the question of the reality of unobservable scientific posits is no longer widely considered a metaphysical question. CE’s suggestion that we should limit our epistemic commitments to the observable, and that unobservable posits play at most a pragmatic role in scientific theorising, do not speak to the question we are addressing here, that of the role, if any, played in science by general metaphysical systems, worldviews, presuppositions, perspectives and so on. The empiricist needs van Fraassen’s stance conception, in addition to CE, to deal with this latter question, and in particular, to provide a means of reconciling the empiricist tradition with an acknowledgement of the central role played by metaphysics in science.
For classic statements and defenses of the distinction, see Hempel (1966, 3-18), Popper (1963, 42-59), and Reichenbach (1938). One of the most famous statements of it is Popper’s: ‘[T]he act of conceiving or inventing a theory seems to me neither to call for logical analysis nor to be susceptible to it… the question of how it happens that a new idea occurs… may be of great interest to empirical psychology; but it is irrelevant to the logical analysis of scientific knowledge.’ Popper, quoted in Ladyman (2002, 75).
One other empiricist philosopher of science who seems to have used the distinction in a similar way is Karl Popper (e.g. 1963, 37-8. See Ladyman 2002, 72). Popper accepts the importance of metaphysical theories in inspiring and helping to generate scientific theories, which is in line with van Fraassen’s view that metaphysical commitments in science may play a potentially valuable role ‘inspiring’ scientists in the context of discovery.
As an interpretation of van Fraassen’s views, this may well be controversial. But what I am mostly concerned with is not whether it perfectly captures van Fraassen’s actual views on science and metaphysics, but how plausible it is. If it is thought to depart significantly from van Fraassen’s actual position, we can rather call it a view ‘inspired by’ his comments on science and metaphysics. I will continue to refer to it as van Fraassen’s position for convenience sake.
Of course, once we construe metaphysical positions as stances rather than factual beliefs, this point follows trivially, since stances are nonpropositional, so are not the kinds of things that may stand in relations of entailment or support. But, setting aside the issue of stances vs. beliefs, it seems to capture van Fraassen’s views about science and metaphysics, e.g. ‘Duhem … saw science as neutral on all issues of metaphysics … Duhem is right, in the main…’ (van Fraassen 1996, 149). ‘[T]here is no nonempirical claim which matters at all to the process of science’ (ibid, 175).
Is this claim descriptive or normative? It is at least normative, that is, a claim about how science ought to proceed. But it is likely that van Fraassen means it to be descriptive as well, that is, a claim about how science does in fact proceed.
See also Wright (1986), who suggests that constitutive of realism are the attitudes of modesty (the world exists independently of us) and presumption (we can know the world).
Thank you to an anonymous referee who urged on me the relevance of NOA to this discussion.
As Longino (1990, 172) puts it: ‘This distinction enables positivists to acknowledge the play of subjective factors in the initial development of hypotheses and theories while guaranteeing that their acceptance remains untainted, determined not by subjective preferences but by observed reality. The subjective elements that taint its origins are purged from scientific inquiry by the methods characteristic of the context of justification: controlled experiments, rigorous deductions, etc.’
Kuhn responds to this sort of defence of the distinction in his (1977), in which he argues that the contamination of the context of justification by subjective, individual, and value-based elements from the context of discovery, is not a contingent matter from which we can abstract to give an admittedly idealised account of the scientific method, but follows necessarily from the very nature of the context of justification itself.
Although see Okruhlik (1994) for a powerful critique of the distinction. Her argument draws on Kuhn, but also on recent feminist philosophy of science. For other discussions of the two contexts, see Kordig (1978), Gutting (1980), Zahar (1983), Leplin (1987), Hoyningen-Huene (1987), and Schickore and Steinle (2006).
As it happens I do think the stance interpretation is plausible in a range of other cases. It’s just that I am not arguing for that here. See conclusion below.
One could hold of course that metaphysical positions sometimes play this role, and sometimes play more of a stance role in van Fraassen’s sense. Thus we should think of the view to which an alternative is being sought as the view that metaphysical positions typically, or characteristically, or at least much of the time, play this sort of role, not that they necessarily always do.
In a television interview Gould (1984) contrasted the punctuationist with the gradualist conception of change: ‘The issue at stake is the very nature of change itself. There is I think a pervasive bias in Western thought to see change as slow, steady, accumulative, gradual, to see change as the essence of nature. There’s another view however, that stability and system and structure is more the essence, and the change, when it occurs, is difficult, that systems absorb stress, and try to maintain themselves, and that every once in a while the stress accumulates to a point where the system breaks and quickly reconstitutes in a new way so that change is not always continuously accumulating, but is rare and episodic, and that systems tend to sit at stable points as much as they can. It’s a different way of viewing the world.’
Gould has not however always clearly drawn this distinction. In the quote from the television interview above for instance, he suggests that ‘the issue at stake’ in the debate over punctuated equilibrium is precisely the nature of change in general.
This is not to deny that there may be some pragmatic incoherence involved in certain combinations of beliefs and metaphysical stances here. van Fraassen (2004b, 173, 176) notes that there can be pragmatic incoherence involved in adopting a stance while denying certain characteristic beliefs naturally or typically associated with it.
It is plausible that there may be at least some pragmatic incoherence involved in, for instance, accepting metaphysical punctuationism while at the same time accepting empirical gradualism, or accepting metaphysical gradualism while accepting punctuated equilibrium.
There may of course be pragmatic inferences in this direction. If metaphysical punctuationism inspired the development of punctuated equilibrium, and the latter is true, this may give us a reason to endorse metaphysical punctuationism as useful, but it doesn’t give us a reason to believe it is true.
The focus here is on social, political and ideological values, but clearly the positions fit with certain epistemic values as well. Metaphysical punctuationism will appeal to those who value non-gradualist forms of explanation, for instance.
Whether Gould holds that metaphysical positions have an epistemically rational dimension is not clear.
This is reminiscent of Feyerabend’s plea for pluralism with respect to metaphysical influences on science. See van Fraassen (1996).
So we do not, for the most part, find him arguing that the truth of punctuated equilibrium gives us a reason to think that metaphysical punctuationism is true and metaphysical gradualism is false (although see interview quote above). But he would presumably endorse the pragmatic inference that the truth of punctuated equilibrium gives us a reason to accept metaphysical punctuationism as useful. I leave aside for now the plausibility of the further, abductive, inference that the best explanation of the usefulness of metaphysical punctuationism is that it’s true.
Boucher (2014) argues that the gene’s eye view, construed in this nonfactual perspective-like way, is a paradigm example of a philosophical stance in van Fraassen’s sense.
‘[T]he biologist should try both ways of thinking, and choose the one he or she prefers’ (ibid, 7).
Compare Rowbottom and Bueno (2011) on stances as ‘styles of reasoning’.
Melnyk (2013, 80) suggests, in response to Shaffer’s metaphysical thesis that the whole is prior to the parts, that there is no scientific reason to suppose there is such a thing as ‘priority’ in this sense. Shaffer is defending monism, not dialectics, but dialectics is similarly committed to the priority of the whole in relation to the parts. Thus this supports the idea that dialectics is lacking in empirical, scientific content.
See Godfrey-Smith (2001), for one of the few discussions of dialectics in mainstream analytic philosophy of biology.
The following have the appearance of being factual beliefs about what the world is like. But we will see that on the stance interpretation, they should rather be understood as expressing a certain mode or style of thinking – what Levins and Lewontin call ‘habits of thought’ and ‘forms of questioning’.
They argue (ibid, 2) explicitly that Cartesian reductionism is both a worldview (factual claim) and a method, and that endorsement of the method is not the same thing as endorsement of the worldview. One assumes they hold the same view about dialectics.
Kitcher (2001, 408, 413) has argued that dialectics fails to offer anything concrete that scientists can use in their day-to-day work. See also Daly, who suggests that Lewontin (and his ally Gould) have failed to effect the paradigm-shift in biology they have desired because they have ‘no alternative research program to offer.’ This is why ‘[s]ufficient research to fill a first issue of Dialectical Biology has yet to materialise’ (Daly, quoted in Dennett 1995, 249). On the stance view I am considering, Kitcher and Daly are right to be sceptical about the prospects for dialectical science, but wrong to thereby dismiss dialectics altogether. They do not recognise that it may play a valuable role as a metaphysical stance in the context of discovery.
Sullivan also suggests that the relationship of predator and prey exemplifies dialectics.
Sullivan’s suggestion (ibid) that dialectics is a ‘heuristic’ that can assist scientists in the process of scientific discovery is quite congenial to the stance position; however he also clearly regards it is as a factual belief that correctly describes the biological world (or certain aspects of it), and is borne out by empirical investigation.
Similarly, we saw that, according to Gould, PE may be accepted by those who do not endorse metaphysical punctuationism.
I have been focusing on niche construction theory, but similar things could be said regarding the broader research program of which it is a part, which has been termed the Extended Evolution Synthesis (ESS) (Laland et al. 2015; Pigliucci 2007). The ideas within the ESS are clearly in the spirit of, and belong to the same tradition as, Lewontin and Levins’ dialectical approach. But again, the existence and importance of the facts, processes and phenomena that adherents of the EES focus on – niche construction, developmental constraints, developmental plasticity, extended inheritance, evolvability, etc. - can be recognised and appreciated independently of dialectical metaphysics, and one need not adhere to dialectics in order to adhere to the ESS. This doesn’t however change the fact that having a dialectical attitude or perspective may make one particularly open or receptive to the ideas of the ESS, and to the extent that the latter are borne out within evolutionary biology, they can help to vindicate the pragmatic utility of the dialectical metaphysical perspective/stance.
Similarly Sober and Wilson argue that the multilevel selection theory they favour enables us to ‘see the whole [evolutionary] stage’ rather than being narrowly focused on a small part of it (1998, 332). It is, they argue, a powerful ‘way of seeing’ with which to view and make sense of facts that are nonetheless accessible (in perhaps less vivid and more obscure and confusing form) from other standpoints. So it is distinctive and valuable not only in virtue of its uncovering of new facts, but also in virtue of the orientation it provides on facts that can be represented from alternative points of view.
‘Whilst some of the world is constituted by dialectical relations, some of it is not. In fact, I would say that the vast majority of the world is not…’ (Sullivan personal communication)
Chakravartty notes that empiricist interpretations of metaphysics and its relation to science are often dismissed as ‘rather severe and ideologically driven rational reconstructions’ (2010, 66). He wasn’t talking specifically about the conception I’m discussing here, but the latter would no doubt be subject to just this sort of criticism.
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Thank you to Terry Sullivan, Greg Restall and Adrian Walsh for helpful comments and criticism.
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Boucher, S.C. An Empiricist Conception of the Relation Between Metaphysics and Science. Philosophia 47, 1355–1378 (2019). https://doi.org/10.1007/s11406-018-0040-4
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DOI: https://doi.org/10.1007/s11406-018-0040-4