Naturalism (philosophy)

Naturalism is a school of philosophy that positions everything as a product of nature, effectively rejecting the concept of the supernatural and attempting to bring the investigation of all philosophical questions into the purview of science and the scientific method. While naturalists deny the concept of the supernatural, which includes traditional Judeo-Christian conceptions of human spirituality, they accept the existence or possibility of phenomena typically classified as supernatural. However, naturalists share the belief that phenomena described as supernatural have an actual basis in natural, scientifically describable reality.

Overview

Though it is most closely associated with the twentieth-century philosophical movement of the same name, naturalism has a much longer precedent in the Western philosophical tradition, which dates to its origins in ancient Greece. Classical thinkers, including Plato (ca. 428 BCE–ca. 347 BCE) and his student Aristotle (384 BCE–322 BCE) pioneered systems of methodological inquiry that heavily influenced the later development of the scientific method. These early systems were built on the premise that natural phenomena follow natural laws, which can be discovered and defined through focused inquiry, logical reasoning, and experimentation. The Dutch-born Portuguese-Jewish philosopher Baruch Spinoza (1632–1677) is also considered a notable foundational contributor to what would come to be recognized as Western naturalism. Considered by experts to be one of the most influential and revolutionary European thinkers of the early modern period, Spinoza forwarded theories of God, the natural world, human existence, and epistemology, notable for incorporating elements now associated with naturalism. Spinoza is especially famous for a fifteen-part proposition that convincingly argues that God represents “the only substance of the universe” (Nadler, 2020), showing that “God is the cause of all things because all things follow causally and necessarily from the divine nature” (Nadler, 2020). This fifteen-point proof, therefore, points to natural causality as the ultimate means of describing and understanding phenomena.

In 1687, Sir Isaac Newton (1643–1727) published The Principia, which is widely recognized as a foundational work in the emergence of modern approaches to scientific inquiry. It “became the paradigm of revolutionary science, providing for the first time a set of simple, mathematically expressed natural laws—the principles of universal gravity, mass, and inertia—that described the movement of material bodies both on earth and in the heavens, which had previously been considered two distinct realms” (Prado, 2006). This breakthrough marked the onset of a flurry of method-based scientific activity that would “extend and unify the realm of natural causation across almost every field of academic investigation” (Prado, 2006). Occurring during a time when religious dogmatism had dominated systemic explanations of the natural world for centuries, it is difficult to overstate the extent to which Newton’s work, and that of his contemporaries and descendants, shifted the Western philosophical paradigm.

Modern science continued its rapid evolution and development over the course of the seventeenth century, and by the Age of Enlightenment in the eighteenth century, scientific reasoning had expanded beyond the confines of scholarly institutions to become a central facet of the era’s culture. The 1859 publication of the seminal scientific work On the Origin of Species, authored by Charles Darwin (1809–1882), marked the next major event in naturalism’s development. The book, “in one stroke, unified the life sciences with the rest of the natural sciences and ended the need to posit supernatural causes in order to explain the order and diversity of nature” (Prado, 2006). It also sparked a direct and bitter conflict between scientific fact and religious belief, which was particularly acrimonious in the United States and played out through politicized events such as the Scopes trial of 1925. The trial centered on the conflict between evolution and creationist theories and their place in US public schools.

It was against this backdrop that naturalism emerged as a specific field of philosophical inquiry. Naturalism emerged as a distinct school of philosophy in the United States during the 20th century, with thinkers like John Dewey (1859–1952), Sidney Hook (1902–1989), Ernest Nagel (1901–1985), and Roy Wood Sellars (1880–1973) among those who pioneered and developed it. Among scholars, Dewey’s contributions to the field are held in particularly high regard, with his system of pragmatic naturalism gaining a high profile that extended beyond intellectual circles into the lay domain. Alternately known as pragmatism, instrumentalism, or cultural naturalism, Dewey’s theory “argued that philosophy had become an overly technical and intellectualistic discipline, divorced from assessing the social conditions and values dominating everyday life” (Hildebrand, 2018). Directly inspired by Darwin’s theory of evolution, Dewey’s pragmatic naturalism attempted to position philosophy “as an activity undertaken by organisms-in-environments” (Hildebrand, 2018), thus drawing strong and direct links between philosophical inquiry, the natural world, and the scientific systems that define and describe it.

A broad look at naturalist philosophies shows that they are based on six main ideas. These ideas are about the nature of existence, knowledge, causality, the self, ethics and morality, and axiology (value theory). On the question of the nature of existence, naturalism holds that human beings and other life forms are “the evolved products of natural selection, which operates without intention, foresight, or purpose” (Clark, n.d.). This viewpoint includes a belief that “[n]othing about [human beings] escapes being included in the physical universe, or escapes being shaped by the various processes ... that science describes” (Clark, n.d.). For naturalists, there is “no evidence for immaterial souls, spirits, mental essences, or disembodied selves that stand apart from the physical world” (Clark, n.d.).

This foundational orientation applies to all other tenets of twentieth-century naturalism, which additionally holds that “knowledge about what exists and about how things work is best achieved through the sciences, not personal revelation or religious tradition” (Clark, n.d.). With respect to causality, naturalists reject the notion of “causal privilege,” instead positing that “nothing causes without being caused in turn” (Clark, n.d.). Notably, this leads naturalists to reject the notion of free will in favor of a belief that all behaviors are instead the products of causative influences. Naturalists extend similar ideas to conceptions of the self, which they describe as mere “products of a physical system, the brain and the body” (Clark, n.d.).

The naturalist denial of free will has profound implications for its views on morality, which hold that because human beings do not have free will and that their actions are instead the result of external causes over which they have often limited or no control, they do not “bear ultimate originative responsibility for their actions” (Clark, n.d.). Yet, at the same time, naturalists believe that societies “must still hold individuals responsible, in the sense of applying rewards and sanctions, so that [human behavior] stays more or less within the range” of social acceptability (Clark, n.d.). Finally, with respect to axiology, the philosophical study of values, naturalists do not “appeal to a supernatural standard of ethical conduct” (Clark, n.d.) as most major religions do and instead consider values and their functions as products of “human needs and desires” (Clark, n.d.).

Further Insights

Reaching the peak of its intellectual influence during the 1930s and 1940s, naturalism developed into a somewhat amorphous and elusive concept after it gained broad acceptance in the modern Western philosophical canon. Commentators note that “[t]he great majority of contemporary philosophers would happily accept naturalism as just characterized—that is, they would both reject ‘supernatural’ entities, and allow that science is a possible route (if not necessarily the only one) to important truths about the ‘human spirit’“ (Papineau, 2020).

On the question of whether the scientific method is the only means by which to gain knowledge about the world and its nature, naturalists generally accept the potential validity of alternative systems. However, in the naturalist paradigm, feasible alternatives cannot be exclusively driven by a priori, or theoretical deductive, methodology. In philosophy, deductive reasoning is based on what are commonly described as “self-evident truths,” which are ideas and principles that follow from linear cause-and-effect reasoning. Naturalists instead believe that sound reasoning inherently follows from direct, observable experience, which is not a precondition for validity in a priori systems.

This division, considered in tandem with the fundamental tenets of naturalist philosophy, has led scholars and commentators to broadly divide naturalism into ontological and methodological components (Papineau, 2020). In philosophy, ontological questions represent a distinctive subfield within metaphysics. While metaphysics deals with all types of principle-based abstractions regarding the origins and first causes of things, ontology specifically focuses on issues related to the nature of existence. Ontological naturalism is “concerned with the contents of reality, asserting that reality has no place for ‘supernatural’ or other ‘spooky’ kinds of entity” (Papineau, 2020). Instead, it focuses on defining causality and methods for classifying and explaining all types of phenomena, including phenomena traditionally considered supernatural, in terms of physical or scientific systems. Over the course of naturalism’s development, this position led thinkers to align themselves with reductive and non-reductive forms of physicalism, in which physicalism is the belief that everything that exists is physical in nature. Reductive physicalism accepts what scholars describe as a “type-identity,” which ties the “strict identity of [a thing’s] relevant special properties [with its] physical properties” (Papineau, 2020). Non-reductive physicalists, meanwhile, “hold that the causal efficacy of special causes will be respected as long as the properties they involve are 'realized by’ physical properties” (Papineau, 2020). The schism essentially highlights disagreements on the ultimate nature of causality.

Another core element of ontological naturalism considers issues of morality. The British philosopher G.E. Moore (1873–1958), who pioneered a related branch of philosophy known as analytical philosophy during the twentieth century, forwarded a famous argument known as the “open question” argument, which is “designed to show that moral facts cannot possibly be identical to natural facts” (Papineau, 2020). The fundamental thrust of Moore’s “open question” argument is that natural properties can never be shown to be either morally good or morally bad, thus making it impossible ever to resolve such an inquiry. Thus, “Moore took this argument to show that moral facts constitute a distinct species of non-natural fact” (Papineau, 2020), which suggests that “moral facts can never make any difference to what happens in the physical world” (Papineau, 2020).

Methodological naturalism, meanwhile, is based on the premise that “philosophy and science [are] engaged in essentially the same enterprise, pursuing similar ends and using similar methods” (Papineau, 2020). In this regard, naturalists recognize an exclusive alignment with posteriori method of reasoning, which represent the opposite of a priori thinking and seek to work backwards from an observed phenomenon or inquiry result in an attempt to understand and define its cause. As such, naturalism problematizes the historically “central role that intuitions play in philosophy” (Papineau, 2020), arguing that the “self-evident truths” supported by a priori reasoning methods created a tradition in which thinkers “assess philosophical views [by] test[ing] them against intuitive judgments about possible cases, not against a posteriori observational data” (Papineau, 2020). Such assessments are inherently at odds with the defining methodologies and theoretical foundations of not only naturalism but also of the broader method-driven mode of scientific inquiry.

During the 1990s, methodological naturalism yielded an analytical paradigm known as the “Canberra plan,” which became highly influential in philosophical circles. Originated by David Lewis (1941–2001), Frank Jackson (1943–), and David Chalmers (1966–), the Canberra plan is based on the premise that “philosophy starts with an initial analysis of concepts employed by everyday thought, such as free will, [or] knowledge, or moral value, or conscious experience” (Papineau, 2020). However, according to the Canberra plan, this basic level of analysis in and of itself fails to describe the ultimate metaphysical sources or “physical ingredients” (Papineau, 2020) of such concepts and experiences. The Canberra plan therefore demands a posteriori explanations, which can only properly be explained in terms of philosophical paradigms based on scientific systems. It broadly endeavors to fill philosophical gaps created by breakdowns in a priori reasoning, which tend to occur at more advanced levels of metaphysical analysis (Braddon-Mitchell & Nola, 2008).

Naturalism has drawn criticism from some philosophers for its over-reliance on the scientific method, which itself is a product of human knowledge. Thus, its critics argue, naturalism bases itself heavily on epistemological presuppositions about the veracity and possible range of understanding that human knowledge has (Szrot, 2015). However, its defenders stress that “naturalism goes beyond science in holding that the vision of ourselves as fully natural creatures has important implications for our place in the world” (Prado, 2006). From this perspective, a “naturalist is someone who, above all, believes that human dignity need not be bought at the price of illusion” (Prado, 2006).

About the Author

Jim Greene is a freelance writer, editor, and content developer with more than twenty years of professional writing experience. Specializing in academic reference, Jim has developed deep expertise as a researcher and an author of digital and print materials covering humanities and social sciences topics. Jim holds an MFA in creative writing from the University of Southern California and a BFA from Toronto Metropolitan University.

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