Naturalism is the term that summarizes the coherent philosophical application and generalization of the methods and conclusions of the sciences. Naturalism is a tendency among thinkers, one that spans most disciplines of thought. Naturalism is not a closely defined school of philosophy, as materialism and idealism have tended to be. Thinkers identified as naturalist often have little else in common.
The principal feature that naturalist thinkers share is an appreciation of the value of grounding their methods in the sciences, because of the heightened chances of securing reliable information, which in turn yields reliable knowledge. Following the thoughts of Dale Riepe, we can make some more specific points: The naturalist places a high value on reason and sense experience as the most reliable avenues of knowledge; the naturalist believes that knowledge is not mystical, innate, or intuitive; the naturalist believes that the external world, of which humans are an integral part, is objective and therefore has existence apart from anyone’s consciousness; and the naturalist believes that the world manifests order and regularity, and that, contrary to some opinions, this does not exclude human responsibility. This order cannot be changed merely by thought, magic, sacrifice, or prayer but requires the actual manipulation of the external world in some physical way. The naturalist also rejects supernatural teleology. The direction of the world is caused by the world itself. And finally, the naturalist is humanistic. Humans are not a mirror of some supernatural deity or absolute principle but a biological existent whose goal it is to do what is proper for humans’ continued existence and fulfillment. These goals can be determined in a naturalistic context by the moral philosopher.
Dale Riepe’s observations were made before embarking on a study of naturalism in Indian philosophy, which illustrates the cross-cultural and transnational nature of naturalism.
This understanding of naturalism involves the rejection of all manifestations of supernaturalism in their capacity as truth-claims on the grounds that they are often culturally specific, whereas naturalist claims are applicable to all nature. Furthermore, supernaturalist claims cannot be repeated, tested, or verified, and in the end, they rely upon mere assertion. However, this does not involve a complete rejection of supernaturalism as a factor worthy of consideration. Supernaturalism is a valid subject of study as a cultural phenomenon within naturalism— a way some people choose to interpret the universe. But it is not an alternative to naturalism.
The most notable feature of naturalism is its transcontinental origins. Where most philosophical systems have their roots in one culture and bear the marks of that culture’s emphases, naturalism can trace its origins back to ancient India, China, and Greece.
A credible case can be made for Uddalaka as the first recorded naturalist. His dates are far from certain, and doubts even about his historicity have been raised. The least unlikely dates for Uddalaka are about 640-610 BCE, which means that he predates the better known Carvakas of India and pre-Socratic Greek philosophers. Uddalaka was a teacher-philosopher who enjoyed disputation and developed a sizable following. He taught that breath was the essential element in a human being. Many idealist thinkers of the time held that thought is the essential element, but Uddalaka argued that thought is itself made up of matter in the same way that breath is. He was also skeptical about reincarnation. Uddalaka provided the first versions of a monistic universe, atomistic physics, and deliberation based on appeal to what is physically observable rather than to mystical slogans.
Shortly after Uddalaka came the Carvakas, the materialist school of thought ( darshana) in India and one of the oldest materialist traditions in the world. Carvaka is thought to be the name of the founder of the school, but nothing is known of him beyond his name, and even his historicity is uncertain. Tradition has Carvaka as the moral accuser of Yudisthira, a leading figure in the Hindu epic, the Mahabharata. Alternatively, Carvaka also means “sweet-tongued,” or “pleasant words,” which may refer to the general perception of Carvaka philosophy as hedonistic.
Carvaka philosophy regards the universe as interdependent and subject to perpetual evolution. Central tenets of the Carvaka school are the following: Sacred literature should be regarded as false; there is no deity or supernatural; there is no immortal soul or afterlife; karma is inoperative and illusory; matter is the fundamental element; and only direct perception, and not religious injunctions or sacerdotal classes, can give us true knowledge. The aim in life is to get the maximum amount of pleasure from it. This had various interpretations, from unalloyed hedonism, on one hand, to an altruistic service of others as a means of maximizing one’s own happiness on the other.
Most authorities acknowledge that the Carvaka tradition has saved Hinduism from lapsing into dogmatism or ritualism and has operated as an important irritant to majority patterns of thought. Although overtly expressed naturalistic thinking in India died out, a naturalistic strand of Indian thought persists to the present day, to the extent that India has no strong moral prohibition against naturalist thinking, which is often a feature of Western thinking.
Chinese thought to this day reflects a naturalistic bent. Chinese thought sees laws in physical nature and in human nature, but has no sense of a supernatural lawgiver. The logician Hui Tzu (380-300 BCE approx., Hui Shih in old spelling) spoke of the universe as “that which has nothing beyond.” This means that all things are part of the universe, the central precept of naturalism. More striking even than this, however, are the concerns of Chinese thinking. Whereas Indian thought is always tempted toward metaphysics, Chinese thought is more about human nature and the ethical imperatives for a sound state, family, and individual. Kongfuzi (551-479 BCE, Confucius in Latinized spelling) urged his readers not to worry about the gods unduly, but to get on with life. Kongfuzi, long recognized as China’s most influential thinker, was concerned with establishing a good society. Such a society can be based only on good government, which in the end relies on harmonious human relations.
In Greece, the earliest naturalist thinker was Thales (approximately 625-545 BCE), who is also credited (not entirely accurately, as we have seen) as the first philosopher. Thales was unprepared to accept the received wisdom about how the universe works. The historian Herodotus tells of a battle that came to an abrupt halt because of an eclipse that took place according to a prediction made by Thales. This established his reputation and, more importantly, the reputation of naturalism as a successful way of understanding the world. The eclipse took place on May 28, 585 BCE, and this date has been given as the day science was born.
Thales was followed by a succession of thinkers that developed different theories of how the universe works. Their theories differed but the thinkers’ desire to understand the world in naturalistic terms brought them together.
For reasons beyond the scope of this topic, the naturalists of India, China, and Greece were overwhelmed by a reaction from idealist philosophers and religious apologists. For almost 2,000 years, the naturalist understanding of the world was dormant. The works of its leading thinkers were destroyed and forgotten, and a dark age of superstition and religious dogmatism spelled an end to the intellectual developments of the ancient world. But although the naturalist world was dormant, it did not die altogether. Some of its works survived and were rediscovered between the 12th and 15th centuries. The rediscovery of the works of the ancients stimulated a renewal of interest in the world and in humanity. The most notable of these flowerings is known as the Renaissance, which took place roughly between the 1370s and 1600, and especially between about 1400 and the 1520s.
Since the Renaissance, naturalism has returned to the center stage of all intellectual and scientific life. Three great revolutions in naturalism have been instrumental in achieving this. The first of these great realignments of thought was what is now called the Copernican revolution. Following discoveries by Copernicus, Kepler, Galileo, and others, no longer was it credible to see Jerusalem, or even the entire planet Earth, as the center of the universe. Instead, it has become apparent that our planet is one among many billions in a universe that is many billions of years old.
The Copernican revolution was followed in the 19th and 20th centuries by the Darwinian revolution, which continued the trend toward the naturalistic outlook becoming the normative way of understanding the universe. If the Copernican revolution meant that humans were no longer the center of the universe, then the Darwinian revolution meant that humans could no longer see themselves as sitting at the peak of the hierarchy of living creatures. The ancient world subscribed to a hierarchy later known as the Great Chain of Being, which went in a line from God or gods, downward through men, then women, higher animals, lower animals, plants, and rocks. But like the earlier habit of seeing the earth as the center of the universe, the Great Chain of Being hierarchy was supported by a supernaturalist outlook that new facts no longer supported. It was now apparent that humans were more like the other animals and shared a planetary ecosystem with them.
The third great naturalist revolution is still unfolding today. It is the revolution in genetics and neurophilosophy, which is rendering obsolete the last major prescientific conceit of our having incorporeal souls and a mind, which is not the same thing as our brain. These three great revolutions in our understanding have elevated naturalism to its current position as the normative outlook for all serious thought.
Cosmological and Methodological Naturalism
But if naturalism has won the day over its pre-scientific predecessors, this does not mean that the intellectual challenges are over. The debate now is centered on the features and priorities of naturalism. Contemporary naturalism is seen as consisting of two aspects, the relations between which are close or not, depending on one’s philosophical outlook. There is, on one hand, cosmological naturalism, which is dedicated to providing a coherent cosmological picture, a worldview that is based on reliable knowledge and without recourse to metaphysics or supernaturalism.
Cosmological naturalism is an outlook on the world that is informed by, although not exclusively composed of, the sciences. John Passmore, one of the 20th century’s greatest historians of philosophy, said that naturalism emphasizes the interconnectedness of things. Cosmological naturalists seek to understand the interconnectedness of things without recourse to supernaturalism or subjectivism. As Richard Dawkins has devoted his career to showing, our orderly universe, a universe indifferent to us as a species “is a more beautiful, more wonderful place than a universe tricked out with capricious ad hoc magic.”
Cosmological naturalism tends to be atheistic or agnostic on matters of the existence of God or gods, and indeed of all other supernatural phenomena. A prime example of cosmological naturalism from the ancient world is De rerum natura (On the Nature of Things), a poem by Lucretius (100-55 BCE) that was completed in 60 BCE. De rerum natura gives expression to the atomist view of the universe as originally expounded by Democritus and adapted by Epicurus. In China, cosmological naturalism has its finest expression in the works of Wang Chong (27-97 CE), whose work Lunheng (Discursive Equilibrium) was written over 82 and 83 CE. Wang Chong argued that natural events are simply that—natural events without any supernatural implications. He opposed the widespread superstitions about attracting fortune to oneself and preventing misfortune. Moral virtue has no essential connection with personal destiny. Wang Chong insisted that any theory must be tested by concrete evidence and tried at all times to argue in a rational manner, supporting his claims with appropriate levels of evidence.
The ideas of Lucretius and Wang Chong have been built on through to the present day and are best represented by philosophers such as Daniel C. Dennett, mathematicians such as Norman Levitt, psychologists such as Steven Pinker, scientists such as E. O. Wilson and Richard Dawkins, and novelists such as Margaret Atwood.
But there is also methodological naturalism, which is not concerned so much with constructing world-views as it is in determining a valid method of acquiring reliable knowledge. This used to be called the “scientific method.” In general terms, we see that the ancient naturalists were more overwhelmingly methodological naturalists than they were cosmological naturalists.
Among contemporary philosophers, Richard Rorty, Hilary Putnam, and Kai Nielsen have been cosmological naturalists without being methodological naturalists. This is usually because of an unwillingness to accord science a privileged position as an arbiter of reliable knowledge. They have sought, in Nielsen’s words, a naturalism without foundations. It is rarer, but not impossible, for people to be methodological naturalists, that is, to accept the use of empirical methods to ascertain reliable knowledge, while not employing that methodology to then build a worldview from it.
One of the main reasons some philosophers wish to distance cosmological from methodological naturalism is that they fear an unwarranted scientism in the methodological program. Kai Nielsen is one of the most recent and lucid articulators of this view. Following Putnam and Rorty, Nielsen questions what is meant by “scientific method,” and he is suspicious about what he sees as a tendency to freeze out art, morality, and religion “while naturalizing them in the spirit of an uncompromising atheism.” However, the writings of those who embrace metaphysical naturalism and methodological naturalism show no sign of this fear having any grounding in fact.
What actually is methodological naturalism? Tad Clements has ascribed the following characteristics: intellectual curiosity; the desire for defensible, reliable knowledge; the tendency to think of the subject of the study as related to other elements of nature in lawful ways, that is, thinking naturalistically; the recognition that anyone may be mistaken; a tendency to skepticism; a predilection toward manipulating conditions so as to be open to experiment; a preference for logical simplicity; an aversion for vague or confused concepts; a preference for the ideal of moral neutrality when seeking knowledge; the tendency to avoid anthropomorphism.
Ironically, these points we have used to itemize methodological naturalism were employed by Clements to illustrate what he called scientific method, so we need not take too seriously differences between the two. And Clements’s account of methodological naturalism carries enough caveats about the uncertainty of our knowledge and the avoidance of unwarranted dogmatism to reassure those worried about the dangers of scientism.
Methodological naturalism needs to overcome two main problems in order to establish its value. First, it needs to demonstrate that the mechanics of methodological naturalism—mathematics and logic—are empirical. And second, it needs to show that nonempirical methodological principles used outside the sciences are unnecessary. The standing of naturalism suffered somewhat during the 1960s and 1970s, when the first of these conditions went through a period of difficulty.
These objections have largely been resolved, and there are now few outside the more radical exponents of science studies or variations of postmodernism who would question the notion that science does involve a gradual accumulation of knowledge, and that we can say we know more now than was known at some point in the past. From this, it follows that we have had more opportunities to weed out error from our account of the universe. That is not to say that our current knowledge is all true, let alone perfect, simply that more is known than was once the case. And to the degree that this is correct, one can speak meaningfully of progress.
The other important point is that science has shown its validity by being the instrument by which so much of this reliable knowledge has come to us. Under the influence of the American philosopher of science Thomas Kuhn, claims like this were problematic for a while in the 1960s and 1970s, but Kuhn’s account was unable to provide an explanation of how scientific knowledge does increase if not by the steady accumulation of knowledge by people working toward a goal of attaining the truth. It ends up that the traditional explanation was right after all: There is an objective reality out there, and, through science, we are slowly getting a better idea of how that reality operates.
Then there is the argument that says that any explanation that goes over and beyond a naturalist explanation violates Occam’s Razor, which requires that we do not unnecessarily multiply entities in explanation. Centuries earlier than William of Occam, the Greek atomists, followed by Strato of Lampsacus, employed Occam’s Razor when they denied that the phenomena of the universe can be explained by appealing to some entity said to be beyond the universe. Antony Flew, following David Hume, has called this the Stratonician Presumption. Flew used this argument in the context of debating the existence of God, but it is clear it has a wider application. Atheistic naturalism, Flew argued, “must have at least this initial priority over theism [because] it is the more economical view. The theist as such postulates more than the atheist; and, in consequence, the onus of proof must rest on him.”
This approach has also been taken up by some prominent scientists and mathematicians. Norman Levitt has argued for what may be called a presumption of science. If the conclusions of science contradict with those of another belief system, then the benefit of doubt goes to the scientific explanation and the burden of proof falls on the supernaturalist explanation. On the face of it, this seems unacceptably arrogant. Why should science be accorded this sort of priority? Levitt’s answer is simple. Because science works and has got an incomparably more reliable track record of providing accurate answers than any other system. Levitt’s claim also becomes more understandable when we recognize that he is not making a distinction between naturalism and super-naturalism as two equally situated systems of thought. He insists that there is no “natural” way to distinguish the natural from the unnatural. In other words, the distinction between nature and culture is itself a cultural construct.
Quentin Smith has advanced a similar argument, but in the interests of the broader concept of naturalism. Smith maintains that naturalists have allowed opponents of naturalism—in his case, theistic apolo-gists—to swing the argument so that theism becomes normative and naturalism becomes marginalized as skepticism about religion. In fact, Smith writes, it is naturalism that is normative, and the various theisms should be seen as skepticisms about naturalism.
As we have seen, Smith’s argument on the normativity of naturalism goes back a long way. Bertrand Russell perhaps understood the problem most clearly when he noted that knowledge is an unimportant feature of the universe, and that a science that omitted to mention knowledge is not going to suffer from any significant imperfection.
What Russell is reminding us is that the universe is a lot larger than is our knowledge of it. Or, to put it more bluntly, anthropocentrism is a serious flaw. It follows, then, that when laying out our intellectual foundations, we must begin with the method of knowledge that is the least inadequate in yielding good quality information about the universe. That has proved to be science. Naturalism is the study of nature in a way that is repeatable and that yields reliable knowledge. Naturalism is, as Paul Kurtz puts it, the philosophical generalization of the methods and conclusions of the sciences. And by virtue of studying nature on its own terms, naturalism avoids, for the most part, the faults that anthropocentrism inevitably brings with it.
This understanding of naturalism does not necessarily equate it with physicalism, which is the claim that only physical entities exist. The claim made by those who are both cosmological and methodological naturalists is not that there are only physical things, but that the methods of study of physical things have yielded the least inadequate information by which we may understand the world. This caveat also has important implications for the alleged conflict between a naturalist and nonnaturalist view of the world, whether it be supernaturalist, idealist, or subjectivist. The emerging discipline of evolutionary psychology is making exciting progress on this question. One of evolutionary psychology’s principal findings is that religions are phenomena of nature, just as gravity, giraffes, and governments are. And like the last of those three examples, religion is also a human creation.
It is rapidly becoming clear that one of the most interesting areas of research and debate in the first half of the 21st century will be the field of naturalistic ethics. As noted earlier, the third great naturalistic revolution involves genetics, the brain, and what being human actually means. The ethical consequences of these fields of study are enormous.
But before beginning any discussion of naturalistic ethics, we need to ask, can we even speak of ethics derived from naturalism at all? Would this not run into the problem of the so-called naturalistic fallacy? This is an important and highly controversial idea, first developed by David Hume, but made known by G. E. Moore (1873-1958) in his 1903 book Principia Ethica. Moore believed that any attempt to define “good” was bound to fail, because “good” is a simple, nonnatural (although not supernatural) quality that could not be analyzed. With this in mind, Moore was critical of some of the social Darwinist theories fashionable at the time that claimed to be able to derive notions of good from their readings of science. Moore drew on the insight of David Hume, who criticized the tendency to draw conclusions about what ought to be the case from information that speaks only about what the case actually is. A graphic example is the tendency of deformed animals to die or be killed by the mother (the “is” in the equation) as evidence that humans suffering from some disability ought to be similarly dealt with.
An important, though neglected, point about the naturalistic fallacy is that it applies not only to naturalistic theories but to all ethical theories. For instance, the claim made by many evangelical Christians that the Bible says X, therefore we ought to X, is an example. So, although the naturalistic fallacy has some worthwhile things to say about the more simple forms of inappropriate is-to-ought rationalizing, it is far from established that any attempt to treat the concept of “good” as something open to analysis is, by definition, mistaken. To take a simple example, polluted water causes illness in people, therefore we ought not to pollute water. Is this really such a bad argument?
We can, therefore, conclude that the naturalistic fallacy serves as a useful corrective to making unduly confident is-to-ought conclusions. But we should not shy away from using science as a tool to help us improve life and happiness on the grounds of a supposed fallacy in philosophy from a century ago.
Having decided that the topic of ethics derived from naturalism is valid, we then need to appreciate fully what is being excluded. All of the conventional items of supernaturalism are abandoned—an incorporeal soul, immortality, resurrection, reincarnation, karma. All of them are removed from consideration because they cannot be validated by any method recognized by methodological naturalism. These precepts are religious ones and are believed as an article of faith and/or cultural practice. This is an important first step, because only now can we see how naturalist ethics works. It also pushes into first place the value of humility, a cosmic humility when one takes on board the implications of being thoroughly unimportant to the cosmos as a whole.
It was Bertrand Russell who articulated this understanding most effectively in some of his ethical writings. Russell urged us to take the longer view. Given that we can’t presume any cosmic reward for ourselves, we must take the longer view and look at what is best for the universe as a whole.
Opponents have frequently criticized this view as “arid,” “bleak,” and lacking in consolation. The last criticism is valid, but the first criticism depends on one’s point of view, and there is no necessary link between the two. What may seem arid to the religious believer is seen as realistic by the naturalist. It is a basic premise of naturalistic ethics that one should not believe in unless one can believe that. In other words, believing something that is untrue but consoling is a fatal subversion of any well-grounded ethics. But this understanding of the cosmos also provides something else with which naturalists are not often credited—an understanding of the tragic sense of life. Miguel de Unamuno (1864-1936) wrote a book by this title that was published just before World War I. However, Unamuno’s understanding of the tragic sense of life was undermined when he then offered the full range of traditional Roman Catholic consolations.
In contrast, the naturalist cannot offer a range of supernaturalist consolations. This understanding has motivated some of the most moving and poignant writing. From Bertrand Russell’s A Free Man’s Worship to Rohinton Mistry’s novel A Fine Balance, some of the more sensitive observers of the human condition have spoken of this fine balance between hope and despair that is the stuff of life. It has been this understanding that has motivated so many of the finest novelists and artists, such as Emile Zola, George Eliot, Arnold Bennett, Maurice Gee, and Iris Murdoch.
Existentialists also understood the central significance of the lack of sustaining consolations, but then could do nothing but counsel despair. Man is condemned to be free, Jean-Paul Sartre wrote, and he himself then spent his life working for political change and helping causes he thought worthwhile. But for so many existentialists, the slogan “existence precedes essence” was taken as an invitation to narcissism. Nothing mattered except creating one’s essence; nothing mattered except oneself. This trend toward narcissism became even more pronounced with the advent of postmodernism, which allowed the next step—nihilism—to present itself. Now, any sort of commitment to a cause or belief larger than oneself was dismissed as little more than an arbitrary snatch at one unwarranted metanarrative rather than another. The only alternatives offered were irony and wallowing in the detritus of a civilization declared by them to be tawdry.
We can now suggest some preliminary conclusions that can be drawn from this survey of naturalist ethics. Of the many articulations of naturalistic ethics, among the clearest was presented in 2003 by Gerald Larue, who also stressed the interconnectedness to which other naturalistic scholars have referred. Larue listed the main conclusions of naturalistic ethics as the following: We are one family, all life forms have had to learn to adapt, and we have a common world ecology.
Larue also concluded that our species has not yet learned to replace our native aggressiveness with aggressiveness for learning about and coming to terms with the limitations of our world ecology.
Naturalism in Art
Before concluding, it is worth returning to the observation made above that naturalism is understood in different ways in different disciplines. We can illustrate this by giving a brief outline of the way naturalism is understood in the visual arts. In the visual arts, naturalism is a term used to refer to the growing interest in portraying objects in nature, particularly the human figure, as the artist actually sees them rather than as exemplars of some ideal.
However, naturalism in art is not to be confused with realism, the accurate representation of nature. Naturalism as a complete and specific style in art reached its apogee in the second half of the 19th century, but naturalistic tendencies or emphases can be seen throughout the history of art. In this way, Egyptian or Assyrian reliefs can be naturalistic in the way human figures are represented, even though the reliefs are by no means realistic accounts of nature. And the romantic paintings of Caspar David Friedrich are naturalistic in their portrayal of nature, even though the inspiration for the paintings owes more to the Romantics.
The specific desire to portray humans naturalistically first found expression during the Renaissance when the idealized figures of Christ or the Virgin Mary were replaced by figures with more human proportions. The work of Leonardo da Vinci (1452-1519) provides the finest illustration of this. It is not that naturalistically rendered works are free from idealization. It is more that whatever ideal values are being presented in the work are transmitted through the representation of people and objects as the artist experiences them.
In conclusion, we can restate the central points that constitute the naturalist worldview. Human knowledge is a fragile flower and forms a less-than-minimal part of the cosmos. From that core assumption, it follows that it is desirable that we adopt a form of knowledge that recognizes its fallibility and resists the temptation to disguise our ignorance by making unverifiable leaps in the dark. The default position goes to the naturalist option for a number of reasons. First, it is most in accord with Occam’s Razor, which leaves supernaturalist systems with the burden of proof. Second, the methods of scientific inquiry are repeatable and testable with regard to circumstances of creed or belief, unlike supernaturalist systems, which are largely dependent on place, time, and station. And third, the record of science in providing reliable knowledge is superior to that of nonnaturalist systems. As such, science contributes most effectively to providing us with some reliable knowledge of the universe, without falling into the temptations of anthropocentrism and anthropomorphism. The worldview that emerges from this process is called naturalism.
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