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Naturalistic Fallacy
Nov 1, 2010

As a metaphysical tenet of speculative philosophy naturalism suggests a worldview that is based on hypotheses that are directed towards an ultimate explanation of nature, the world observed. The principal assumption in naturalistic discourse is that nature is autonomous, that is, it is independent of supernatural influences like divine creation. The assumed autonomy of nature, which might be called the “naturalistic principle,” can be found in various proportions in diverse forms of this tenet. Relative kinds of naturalism, like that in Deism-the idea that God granted nature with autonomy, thus not being its master anymore-are outside the concern of this essay. By the term “naturalism” I am referring to what might be called “absolute naturalism,” the notion that nature is the only reality, and thus absolutely autonomous; this idea can be observed in materialism or physicalism in their radical form. My aim is to point out the inherent fallacy of this notion, namely the unreasonable reduction of reality into the world observed. Basically some exemplary statements that are set forth to define the notion will be examined here. I intend to indicate that naturalism not only suffers from inherent existential and moral troubles, but that it also collapses due to the logical fallacy on which it is based.

The twisted grammar of the naturalistic fallacy

In assuming nature to be uniquely real, a naturalist proposes that “reality” (or “existence”) means “natural being” and nothing more. Instead of saying, “nature is real,” (or “nature exists,”) a naturalist prefers to says, “reality (or existence) is nature.” Such an utterance has an odd syntax, with the subject and predicate being strangely exchanged, thus twisting the grammar and invalidating it. It is not vague, but rather nonsensical. Such nonsense originates from the awful mistake of reducing a group (here, “beings”) into a member (“natural beings”), or, to use logical terms, equating a universal (here, “reality” or “existence”) to a particular (“natural reality” or “natural existence”). What a naturalist attempts here is to narrow the meaning of reality; this can be called “naturalistic fallacy,” borrowing G. E. Moore’s phrase. It is with this attempt that naturalism becomes unreasonable. Namely, as it is reasonable to conceive of “unnatural” beings, that is, any entities outside the world observed, it is thus unreasonable to assume nature as being unique in reality. In other words, the “world observed” is not equal to (nor does it consume the meaning of) the world of reality. The phrase “natural existence” is a necessary reference to-at least the possibility of-“unnatural existence.” Indeed, against this immediate inquiry of justification, naturalistic discourse does nothing but recede from a logical base. As the famous naturalist Kai Nielsen states, naturalism is nothing but an idea without any idea of foundation. That is to say, naturalism remains as arbitrary as any fantastic speculations about an alien world, as both share the same status of justification.

Hetoric divorced from logic

(a) “Naturalism is the view that only natural objects, kinds, and properties are real.”

As “natural” here is used to mean “of the world observed,” then the use of “only” means that “real” cannot be the proper predicate for the sentence. This statement is odd. To perceive the oddity, imagine (if possible) a man who understands the concept of “color” but is unable to perceive anything except red objects. Had such man said, “Only red is a color,” this is then equal to “All color is red.” Similarly, a naturalist suggests imagining reality as “comprising” (not “including”) nature. Can you imagine yourself answering this question: “Do you know why birds are eagles?”

(b) “Naturalism is the belief that the world is a single system of things or events, every one of which is bound to every other in a network of relations and laws, and outside this natural order there is nothing.”

If one were to ask a naturalist what convinced them to view the world as a single system that excludes unnatural things, they would answer, “The fact that I haven’t seen such things.” Responding thus, they admit the possibility of unnatural realities, which fulfills the meaning of the phrase “outside this natural order” in the statement. If a child asks this naturalist what might happen outside the natural order, how meaningful it is if they reply: “I have no idea” and how meaningless if they reply: “Nothing.” Such a conversation would demonstrate that it is impossible to place nature into “space” as a concept of physics, and that it is certainly not a childish attempt to try to squeeze reality into nature.

Groundless denial of supernatural

(c) “Naturalists reject all such notions of spirits, disembodied souls, non-material personal gods, and more-than-natural agencies. The grounds for the rejection of these notions are a lack of evidence adequate to support these notions.”

Ideas of spirits or souls are referred to as “supernatural” in that they are “ordinarily” not subject to the world observed. This means that they might be subject to the world of phenomena or of experience. There may be (reportedly, are) many experiences regarding supernatural phenomena, like spirits, angels, inspirations, revelations, etc. If this is the case then it would be unreasonable to reject all the relevant human traditions. Just as a momentary sighting of a peculiar insect is sufficient reason for the conviction that there is such a species on earth, the same is true for more peculiar entities. This indicates, as William R. Dennes clearly puts, that naturalists may have no reason to exclude intelligible reference to supernatural. Had a child reported to a naturalist that he had certainly seen a ghost, or that his dead grandfather had related a secret to him in dream, but the naturalist denies the child’s claims, accusing him of lying or dreaming, then the child’s rejection, in turn, of all the stories told and all the advice given by the naturalist that are based on experience would be meaningful.

(d) “Naturalism denies that there are any supernatural or spiritual realities. There are no purely mental substances and there are no supernatural realities beyond nature or transcendent to the world or anything of the sort, or at least we have no sound reasons for believing that there are such realities or perhaps even that there can be such realities. Physical realities, or perhaps as well realities dependent on physical realities, are the only kind of realities there are.”

The problem in the above statement is that the non-existence of supernatural entities cannot be reasonably claimed, let alone proven. Common sense commands that we not deny any possibility unless logically necessary. In logic, the denial of possibility is one of the two greatest mistakes; the other is the refusal of necessity. It seems that a naturalist cannot maintain such mistakes forever as they would necessarily encounter some form of supernatural experience, just as other fellow humans are. In other words, conjectures die away whenever phenomena manifest themselves. A naturalist then cannot be serious in his materialistic position, in denying the most manifest supernatural phenomenon, the soul, the factual manifestation of which is consciousness and the conscience. Therefore, rejecting any “purely mental substance” is a sophistic proposition. The immutable duality of “subject” and “object” always warrants the fact that “soul” is the constant interference of the supernatural into natural. Namely, if “nature” is the object that is observed, “I” am the subject that observes. Here we infer that a naturalist can only pretend to become a materialist at the expense of their own self. As Schopenhauer once wrote, materialism is the philosophy of the “subject” that forgets to give account of himself.

A pointless appeal to natural science

(e) “Naturalism is the recognition that it is within science itself, and not in some prior philosophy, that reality is to be identified and described.”

If science is claimed, in this approach, to identify reality, that is, to assign by observation what is real and what is not, then science itself is at stake as the objective study of natural reality, merely because it is the concept of reality that justifies observation. Plainly speaking, it is the sense of “real” that qualifies observation, not the opposite. This is why it is meaningful to say, “What we observe is real.” It is impossible to identify anything without having a “prior” conception of reality. In Kant’s dictionary, it is a priori concepts, the most prior of which is “reality,” that ensure all a posteriori notions, which all scientific terms are subject to. Now, upon this logical structure it is meaningful for a child to ask: “Aren’t ghosts real?” as well as for a naturalist to reply: “Certainly, not!” Similarly, natural science asks: “How is natural reality?” and answers: “It is in accordance with observation.” Thus, science admits that the reality of nature needs to be identified by a prior philosophy, a metaphysical notion. This means that natural science normally denounces (scientists must denounce) the awful illusion of scientism, the claim that science is uniquely eligible to identify the reality of the world; it is in regard with this that Wittgenstein warns that “the whole modern conception of the world is founded on the illusion that the so-called laws of nature are the explanations of natural phenomena.” What the philosopher means is that a scientist is no wiser about nature than anyone else when he steps out of his laboratory.

A final word

One may gather from this brief analysis that naturalism, in its absolute form, is destined to struggle forever, if not pass away, with the irremovable fallacy of reductionism. A naturalist may understand that to avoid from this destiny they must abandon the vacuous attempt to “invent” a logic for the world, rather maintaining the language on the grammar of possibility when assuming metaphysics, by stating, for instance, “Nature may be autonomous; who knows?” Such normalization turns naturalism, as Kai Nielsen states, into a game that might be called “fallibilism” and must be played without any confidence or hope. As a result, for anybody who wants to take metaphysics seriously for their ultimate concerns, as Michael C. Rea emphasizes, there is no such an option as naturalism.

Erkan Mazhar Kurt has a PhD in theology. He is an executive member of The Institute of Interfaith Dialog, Houston, Texas.


1. See, William Ray Dennes, Some Dilemmas of Naturalism, Columbia University Press, New York 1960, p. 80.

2. Kai Nielsen, Naturalism without Foundations, Prometheus Books, New York 1996, p. 35.

3. See, Michael C. Rea, World without Design: The Ontological Consequences

of Naturalism, Clarendon Press, Oxford 2002, p. 56. (These and the following emphases are mine for attention at conceptual relations.)

4. See, ibid, p. 55.

5. Cf. Ludwig Wittgenstein, Tractatus Logico-Philosophicus (tr. D. F. Pears & B. F. McGuinness), Routledge & Kegan Paul, London 1961, p. 149.

6. Sterling P. Lamprecht, The Metaphysics of Naturalism, Meredith Publishing

Company, New York 1967, p. 209.

7. Dennes, ibid, p. 21.

8. Nielsen, ibid, p. 25.

9. Cf. Robert Sokolowski, Introduction to Phenomenology, Cambridge University Press, New York 2000, p. 14.

10. Cf. A. D. Smith, “Non-Reductive Physicalism?” in Objections to Physicalism

(ed. Howard Robinson), Oxford 1993, p. 225.

11. Cf. Ralph Walker, “Transcendental Arguments against Physicalism” in Objections to Physicalism (ed. Howard Robinson), Oxford 1993, p. 78.

12. Arthur Schopenhauer, The World as Will and Representation (tr. E. F. J. Payne), Massachusetts 1958, II, 313.

13. See, Rea, ibid, p. 42.

14. Cf. Dallas Willard, “Knowledge and Naturalism” in Naturalism: A Critical Analysis (ed. William Lane Craig & J. P. Moreland), Routledge, New York 2000, p. 30.

15. See, Immanuel Kant, Critique of Pure Reason (tr. J. M. D. Meiklejohn), Prometheus Books, Buffalo 1990, p. 7.

16. Wittgenstein, ibid, p. 143.

17. Cf. Ian G. Barbour, Religion and Science: Historical and Contemporary Issues, HarperSanFrancisco, New York 1997, p. 87.

18. Nielsen, ibid, p. 26.

19. Rea, ibid, p. 59.