What is Naturalism?

The term “naturalism” has widely and confidently been used in a wide array of areas in philosophy. But only in rare instances do phi-losophers take the time to explicate what is implied by identifying as a “naturalist.” One can account for most usages of this term by bifur-cating naturalism into modest naturalism and scientific naturalism.

Modest naturalism is characterized by two aspects. First, modest naturalism implies science´s independence from philosophy. In contrast, the traditional notion of philosophical foundationalism attributed to philosophy a foundational role. According to philo-sophical foundationalism, philosophy is an a priori inquiry into the nature of reality, and stands in a foundational relation to the sciences. That idea is at least a minimal criterion for the notion of naturalism: philosophy does not provide the foundations for the scientific disciplines. It is indeed hard to find philosophers in the 20^th and 21^st century who assert that philosophy has authority over the sciences. Instead, virtually any philosopher will assert that the sciences work well without philosophical guidance of any sort. In the current intellectual environment, it seems indeed hopeless to defend the claim that philosophy is in a position to dictate to the sciences ex cathedra. Note that this is a negative claim about what the relation between philosophy and science is not, but not a posi-tive claim about how to conceive this relation.

Second, modest naturalism implies a rejection of supernatural-ism. Naturalism shuns supernatural things from philosophy. Super-naturalism is the belief that “there are entities that lie outside of the

normal course of nature.” Supernatural entities are those “whose existence cannot be countenanced by (natural) science.”⁸ Common examples for such supernatural entities are: ghosts or goblins or fairies or other kinds of things connected to magic or witchcraft.

But it also includes “immaterial minds or souls, vital fluids, angels, and deities.”⁹ But there are two problems with setting this up. First, the conception of what counts as supernatural is not clear-cut in a way that makes it interesting for philosophy. For example, although the latter examples given are immaterial phenomena, supernatural-ist entities cannot be identified with immaterial things since num-bers and governments are also immaterial, but not supernatural.

Someone wanting to classify numbers and governments as super-natural (because they are not physical) would have to offer substan-tial argument to make this view plausible. Clearly, naturalism has to allow for numbers, at least, since numbers are necessary tools in any natural science which, according to naturalism, enjoy a privileged position. It is simply not sufficient to reject supernatural entities if one wants to call oneself a “naturalist.” Second, it is indeed hard to find a philosopher who would assert the existence of witchcraft or deities at all. Just like with a supposed superiority of philosophy over science, defending this form of supernaturalism today seems hopeless to most. So while the vast majority of philosophers will deny the existence of supernatural entities, the attitudes towards abstract objects are more complicated. Most philosophers, includ-ing self-identifyinclud-ing naturalists, will somehow want to account for abstract entities rather than deem them supernatural. In short: A working, substantial notion of naturalism needs to feature a crite-rion that specifies what it means for something to be natural.

Ultimately, modest naturalism is uncontroversial, and hence useless when trying to substantiate the term “naturalism.” If “nat-uralism” just meant “modest nat“nat-uralism” almost everybody was a

7 John Dupré, “The Miracle of Monism,” in Naturalism in Question, ed. Mario de Caro and David Macarthur (Harvard: Harvard University Press, 2008), 36–58.

8 Henrik Rydenfelt, “Naturalism and Normative Sciences,” in Pragmatism, Science, Naturalism, ed. Henrik Rydenfelt and Jonathan Knowles (Bern: Peter Lang, 2011), 115.

9 Dupré, “The Miracle of Monism,” 36. Another, nowadays rather unpopular example would be: God.

naturalist by default. This leaves scientific naturalism up for con-sideration. Scientific naturalism, too, is characterized by two differ-ent aspects: a methodological and an ontological aspect. The first, methodological aspect states that scientific naturalism, too, rejects philosophical foundationalism. Philosophical foundationalism is the view that philosophy provides epistemological and metaphys-ical foundations for science. Instead, scientific naturalism claims that philosophy has no authority over science. So far, this amounts to the same methodological claim as that of modest naturalism. But beyond that, scientific naturalism claims continuity of philosophy and science by claiming generality of the scientific method such that philosophical inquiry is in principle continuous with science. While philosophy should cede areas of inquiry to the sciences whenever possible, philosophy and science work on the same project, with similar means and ends.¹⁰ In this sense, philosophy “is science in its general and abstract reaches.”¹¹ By assuming this substantial rela-tion, a scientific naturalist diverges from a modest naturalist regard-ing metaphilosophical views. The second, ontological aspect states:

all that truly exists in the world are those basic entities discovered by (the methodologies and practices of) science. All other phenom-ena must be in some way related to scientifically respectable entities in a suitable way.¹² In a diagrammatic representation, scientific nat-uralism can be characterized as follows:

Scientific naturalism = ontological aspect + methodological aspect

The methodological aspect given here is a refined phrasing of the Quinean denial of first philosophy, the idea of “abandonment of the

10 Papineau, “Naturalism.”

11 Mario de Caro and David Macarthur, Introduction, “The Nature of Naturalism,” in Naturalism in Question, ed. Mario de Caro and David Macarthur (Harvard: Harvard University Press, 2008), 6.

12 A similar, yet more specific description is: “every real entity either consists of or is somehow ontologically grounded in the objects countenanced by the hypothetically completed empirical sciences […].” See Paul Moser and David Yandell David, “A Farewell to Philosophical Naturalism,” in Naturalism: A Critical Analysis, ed. William Craig and J.P. Moreland (London: Routledge, 2000), 4.

goal of a first philosophy prior to natural science,” meaning that science “is not answerable to any supra-scientific tribunal, and not in any need of justification beyond observation and the hypotheti-co-deductive method.¹⁴ This claim be rephrased such that “science cannot be based on a foundation more secure than itself.”¹⁵ The Ontological aspect on the other hand is a simpler phrasing of Sel-lars´ scientia mensura-statement already alluded to above: “Science is the measure of all things, of what it is that it is, and of what is not that it is not.”¹⁶

I do not purport that only he or she who undertakes the meth-odological and ontological commitment jointly is a scientific natu-ralist, and that someone who – overtly – only accepts one of them is not. Not every scientific naturalist overtly endorses both commit-ments. In practice, it may be harder to group together those phi-losophers who either endorse only one of these commitments with those philosophers who endorse all of them respectively. But for the current purpose, a higher grade of exactness is not needed here.