Naturalism (philosophy)

This article is about the term that is used in philosophy. For other uses, see Naturalism (disambiguation).

Naturalism commonly refers to the philosophical viewpoint that the natural universe and its natural laws and forces (as opposed to supernatural ones) operate in the universe, and that nothing exists beyond the natural universe or, if it does, it does not affect the natural universe that we know. Followers of naturalism (naturalists) assert that natural laws are the rules that govern the structure and behavior of the natural universe, that the universe is a product of these laws and that the goal of science is to discover and publish them systematically.

Note that the term "naturalist" is also used to describe a person involved with natural history, the scientific study of (or education about) nature and the natural world (particularly fields of botany and zoology), as distinct from someone holding any specific philosophical position.

Philosopher Paul Kurtz argues that nature is best accounted for by reference to material principles. These principles include mass, energy, and other physical and chemical properties accepted by the scientific community. Further, this sense of naturalism holds that spirits, deities, and ghosts are not real and that there is no "purpose" in nature. This sense of naturalism is usually referred to as metaphysical naturalism or philosophical naturalism.

Theists challenge the idea that nature is all there is. They believe in a god (or gods) that created nature. Natural laws have a place in their theology; they describe the effects of so-called secondary causes (see History section, below). But, natural laws do not define nor limit the deity(ies), who is the primary cause.

In the 20th century, W.V. Quine, George Santayana, and other philosophers argued that the success of naturalism in science meant that scientific methods should also be used in philosophy. Science and philosophy are said to form a continuum, according to this view.

History

The ideas and assumptions of philosophical naturalism were first seen in the works of the Ionian pre-Socratic philosophers. One such was Thales, considered to be the father of science, as he was the first to give explanations of natural events without the use of supernatural causes. These early philosophers subscribed to principles of empirical investigation that strikingly anticipate naturalism.

The modern emphasis in methodological naturalism primarily originated in the ideas of medieval scholastic thinkers during the Renaissance of the 12th century:

By the late Middle Ages the search for natural causes had come to typify the work of Christian natural philosophers. Although characteristically leaving the door open for the possibility of direct divine intervention, they frequently expressed contempt for soft-minded contemporaries who invoked miracles rather than searching for natural explanations. The University of Paris cleric Jean Buridan (a. 1295-ca. 1358), described as "perhaps the most brilliant arts master of the Middle Ages," contrasted the philosopher’s search for "appropriate natural causes" with the common folk’s habit of attributing unusual astronomical phenomena to the supernatural. In the fourteenth century the natural philosopher Nicole Oresme (ca. 1320–82), who went on to become a Roman Catholic bishop, admonished that, in discussing various marvels of nature, "there is no reason to take recourse to the heavens, the last refuge of the weak, or demons, or to our glorious God as if He would produce these effects directly, more so than those effects whose causes we believe are well known to us."

Enthusiasm for the naturalistic study of nature picked up in the sixteenth and seventeenth centuries as more and more Christians turned their attention to discovering the so-called secondary causes that God employed in operating the world. The Italian Catholic Galileo Galilei (1564–1642), one of the foremost promoters of the new philosophy, insisted that nature "never violates the terms of the laws imposed upon her."

During the Enlightenment, a number of philosophers including Francis Bacon and Voltaire outlined the philosophical justifications for removing appeal to supernatural forces from investigation of the natural world. Subsequent scientific revolutions would offer modes of explanation not inherently theistic for biology, geology, physics, and other natural sciences.

Pierre Simon de Laplace, when asked about the lack of mention of God in his work on celestial mechanics, is said to have replied, "I have no need of that hypothesis."

The current usage of the term naturalism "derives from debates in America in the first half of the last century. The self-proclaimed ‘naturalists’ from that period included John Dewey, Ernest Nagel, Sidney Hook and Roy Wood Sellars." For them nature is the only reality. There is no such thing as 'supernatural'. The scientific method is to be used to investigate all reality, including the human spirit: “So understood, ‘naturalism’ is not a particularly informative term… The great majority of contemporary philosophers would happily… reject ‘supernatural’ entities, and allow that science is a possible route (if not necessarily the only one) to important truths about the ‘human spirit’.”

The term "methodological naturalism" for this approach is much more recent. According to Ronald Numbers, it was coined in 1983 by Paul de Vries, a Wheaton College philosopher. De Vries distinguished between what he called "methodological naturalism," a disciplinary method that says nothing about God's existence, and "metaphysical naturalism," which "denies the existence of a transcendent God." The term "methodological naturalism" had been used in 1937 by Edgar S. Brightman in an article in The Philosophical Review as a contrast to "naturalism" in general, but there the idea was not really developed to its more recent distinctions.

Metaphysical naturalism

Main article: Metaphysical naturalism

Metaphysical naturalism, also called "ontological naturalism" and "philosophical naturalism", is a philosophical worldview and belief system that holds that there is nothing but natural elements, principles, and relations of the kind studied by the natural sciences, i.e., those required to understand our physical environment by mathematical modeling. Methodological naturalism, on the other hand, refers exclusively to the methodology of science, for which metaphysical naturalism provides only one possible ontological foundation.

Metaphysical naturalism holds that all properties related to consciousness and the mind are reducible to, or supervene upon, nature. Broadly, the corresponding theological perspective is religious naturalism or spiritual naturalism. More specifically, metaphysical naturalism rejects the supernatural concepts and explanations that are part of many religions.

Methodological naturalism

Methodological naturalism is concerned not with claims about what exists but with methods of learning what is nature. It is strictly the idea that all scientific endeavors—all hypotheses and events—are to be explained and tested by reference to natural causes and events. The genesis of nature, e.g., by an act of God, is not addressed. This second sense of naturalism seeks only to provide a framework within which to conduct the scientific study of the laws of nature. Methodological naturalism is a way of acquiring knowledge. It is a distinct system of thought concerned with a cognitive approach to reality, and is thus a philosophy of knowledge. Studies by sociologist Elaine Ecklund suggest that religious scientists do in fact apply methodological naturalism. They report that their religious beliefs affect the way they think about the implications, often moral, of their work, but not the way they practice science.

In a series of articles and books from 1996 onwards, Robert T. Pennock wrote using the term methodological naturalism to clarify that the scientific method confines itself to natural explanations without assuming the existence or non-existence of the supernatural, and is not based on dogmatic metaphysical naturalism as claimed by creationists and proponents of intelligent design, in particular Phillip E. Johnson. Pennock's testimony as an expert witness at the Kitzmiller v. Dover Area School District trial was cited by the Judge in his Memorandum Opinion concluding that "Methodological naturalism is a "ground rule" of science today":

"Expert testimony reveals that since the scientific revolution of the 16th and 17th centuries, science has been limited to the search for natural causes to explain natural phenomena.... While supernatural explanations may be important and have merit, they are not part of science." Methodological naturalism is thus "a self-imposed convention of science." It is a "ground rule" that "requires scientists to seek explanations in the world around us based upon what we can observe, test, replicate, and verify."

Philosophers on methodological naturalism

Alvin Plantinga

Alvin Plantinga is a Professor of Philosophy, formerly at Notre Dame University and now at Calvin College. He is a serious Christian and a well-known critic of naturalism. In a paper entitled Methodological Naturalism?, he argued that:

... a Christian academic and scientific community ought to pursue science in its own way, starting from and taking for granted what we know as Christians.... Hence the sorts of hypotheses we investigate might very well involve such facts (as the Christian thinks) as that we human beings have been created by God in his image, and have fallen into sin. These religious ideas might take a place in our science by way of explicitly entering various hypotheses. They might also play other roles: for example, they might be part of the background information with respect to which we evaluate the various scientific hypotheses and myths that come our way.

Not surprisingly, Plantinga objects to Judge Jones decision in the Kitzmiller trial that "methodological naturalism is a 'ground rule' of science today" and that "supernatural explanations [e.g., God did it] ... are not part of science." Plantinga questions whether a definition (of science) can be the basis of a judicial decision. He notes that there are many different "constraints" that can define science, e.g., "the aim of science is explanation," moral judgments are excluded, etc. He wrote:

And what does "science" really mean? ... the following seems sensible: The usual dictionary definitions suffice to give us the meaning of the term "science." They suggest that this term denotes any activity that is:

(a) a systematic and disciplined enterprise aimed at finding out truth about our world, and

(b) has significant empirical involvement.

Any activity that meets these vague conditions counts as science.

....

But what about methodological naturalism...?

What are the advantages and disadvantages of doing science in accord with methodological naturalism? There is a good deal to be said on both sides here. For example, if you exclude the supernatural from science, then if the world or some phenomena within it are supernaturally caused - as most of the world's people believe - you won't be able to reach that truth scientifically.

Observing methodological naturalism thus hamstrings science by precluding science from reaching what would be an enormously important truth about the world. It might be that, just as a result of this constraint, even the best science in the long run will wind up with false conclusions.

A recent letter (2010) suggests that Plantinga accepts that methodological naturalism defines at least one kind of science:

But the scientific theory of evolution, sensibly enough, says nothing one way or the other about divine guidance. It doesn't say that evolution is divinely guided; it also doesn't say that it isn't. Like almost any theist, I reject unguided evolution; but the contemporary scientific theory of evolution just as such - apart from philosophical or theological add-ons - doesn't say that evolution is unguided. Like science in general, it makes no pronouncements on the existence or activity of God."

Michael Ruse

Michael Ruse wrote his essay Methodological Naturalism under Attack to reply to Plantinga's essay on Methodological Naturalism? quoted above. Ruse wrote:

...one has a notion or a practice that can properly be called "methodological naturalism": although this is the working philosophy of the scientist, it is in no sense atheistic as such. The methodological naturalist is the person who assumes that the world runs according to unbroken law; that humans can understand the world in terms of this law; and that science involves just such understanding without any reference to extra or supernatural forces like God. Whether there are such forces or beings is another matter entirely, and simply not addressed by methodological naturalism.

Robert T. Pennock

Robert T. Pennock contends that as supernatural agents and powers "are above and beyond the natural world and its agents and powers" and "are not constrained by natural laws", only logical impossibilities constrain what a supernatural agent could not do, and "If we could apply natural knowledge to understand supernatural powers, then, by definition, they would not be supernatural". As the supernatural is necessarily a mystery to us, it can provide no grounds on which to judge scientific models. "Experimentation requires observation and control of the variables.... But by definition we have no control over supernatural entities or forces." Science does not deal with meanings; the closed system of scientific reasoning cannot be used to define itself. Allowing science to appeal to untestable supernatural powers would make the scientist's task meaningless, undermine the discipline that allows science to make progress, and "would be as profoundly unsatisfying as the ancient Greek playwright's reliance upon the deus ex machina to extract his hero from a difficult predicament."

Naturalism of this sort says nothing about the existence or nonexistence of the supernatural, which by this definition is beyond natural testing. As a practical consideration, the rejection of supernatural explanations would merely be pragmatic, thus it would nonetheless be possible, for an ontological supernaturalist to espouse and practice methodological naturalism. For example, a scientist may believe in God, while practicing methodological naturalism in their scientific work. This position does not preclude knowledge that is somehow connected to the supernatural. Generally however, anything that can be scientifically examined and explained would not be supernatural, simply by definition.

The National Academy of Sciences

"In the book Science, Evolution, and Creationism, a group of experts assembled by the National Academy of Sciences and the Institute of Medicine explain the fundamental methods of science ...." Essentially, it affirms methodological naturalism:

In science, explanations must be based on naturally occurring phenomena. Natural causes are, in principle, reproducible and therefore can be checked independently by others. If explanations are based on purported forces that are outside of nature, scientists have no way of either confirming or disproving those explanations. Any scientific explanation has to be testable - there must be possible observational consequences that could support the idea but also ones that could refute it. Unless a proposed explanation is framed in a way that some observational evidence could potentially count against it, that explanation cannot be subjected to scientific testing.

See also

• American Atheists
• Bonum sane
• Brights movement
• Empiricism

• George Santayana
• Internet Infidels
• Materialism
• Metaphysical naturalism

• Naturalism (literature)
• Naturalistic pantheism
• Physicalism
• Physical ontology

• Positivism
• Religious Naturalism
• Sociological naturalism
• Supernaturalism

References

• Audi, Robert (1996). "Naturalism". In Borchert, Donald M.. The Encyclopedia of Philosophy Supplement. USA: Macmillan Reference. pp. 372–374. 
• Danto, Arthur C. (1967). "Naturalism". In Edwords, Paul. The Encyclopedia of Philosophy. New York: The Macmillan Co. and The Free Press. pp. 448–450. 
• Kurtz, Paul (1990). Philosophical Essays in Pragmatic Naturalism. Prometheus Books. 
• Lacey, Alan R. (1995). "Naturalism". In Honderich, Ted. The Oxford Companion to Philosophy. Oxford University Press. pp. 604–606. 
• Post, John F. (1995). "Naturalism". In Audi, Robert. The Cambridge Dictionary of Philosophy. Cambridge University Press. pp. 517–518. 
• Sagan, Carl (2002). Cosmos. Random House. ISBN 978-0375508325. 

Further reading

• Mario De Caro and David Macarthur (eds) Naturalism in Question. Cambridge, Mass: Harvard University Press, 2004.
• Mario De Caro and David Macarthur (eds) Naturalism and Normativity. New York: Columbia University Press, 2010.
• Friedrich Albert Lange, The History of Materialism, London: Kegan Paul, Trench, Trubner & Co Ltd, 1925, ISBN 0-415-22525-6
• David Macarthur, “Quinean Naturalism in Question,” Philo. vol 11, no. 1 (2008).

External links

Supportive

• naturalism.org
• Naturalist Newsletter
• Center for Naturalism
• Naturalism: The Naturalistic Worldview
• Naturalism David Papineau, The Stanford Encyclopedia of Philosophy
• The Brights Illuminating and elevating the naturalistic worldview

Neutral

• The Craig-Taylor Debate: Is The Basis Of Morality Natural Or Supernatural? William Lane Craig and Richard Taylor October 1993, Union College (Schenectady, New York)
• Naturalism Jon Jacobs, The Internet Encyclopedia of Philosophy

Critical

• Naturalism article in the Catholic Encyclopedia
• Dennis Polis, God, Science and Mind: The Irrationality of Naturalism
• Alvin Plantinga (1994). Naturalism Defeated. http://www.calvin.edu/academic/philosophy/virtual_library/articles/plantinga_alvin/naturalism_defeated.pdf.  (pdf)
• A shorter version of C. S. Lewis' Dangerous Idea
• Philip Johnson's Evolution as Dogma: The Establishment of Naturalism from First Things
• Robert A. Delfino's (2007) Replacing Methodological Naturalism

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