1A central issue in contemporary philosophy of mind is understanding how mind fits into the natural world. This challenge becomes particularly evident when considering how subjective experiences, such as qualia and sensations, arise from brain processes. When I touch an ice cube, I feel a unique sensation of coldness; when I taste coffee, I experience the distinct flavor of coffee. Whether science can explain such subjective qualia has become a key point of debate between physicalists and dualists. Scientific physicalists believe that qualia are physical and can be theoretically explained by science. Dualists, however, claim that these qualia are fundamental features of the world that cannot be reduced to physical properties and, therefore, cannot be fully explained by current scientific theories. For physicalists, the issue of qualia represents one of the biggest challenges to their position. Among the various issues in the philosophy of mind, the problem of qualia often triggers the strongest intuitive resistance. Whether one takes the eliminative materialist stance that qualia don’t exist at all or the non-reductionist view that they depend on brain activity, the question remains unresolved. For over half a century, both scientists and philosophers have grappled with how first-person qualia can be adequately explained using the third-person perspective of science.
2In Philosophy and the Scientific Image of Man, Wilfrid Sellars presents two frameworks for understanding: what he calls the “manifest image” versus the “scientific image.” The manifest image, which reflects everyday human experience and intuitive perceptions of the world, such as the belief in autonomous decision-making when discussing concepts like “free will.” The scientific image, according to Sellars, is based on theoretical constructs and scientific analysis, challenging intuitive understandings from the manifest image. For example, behavioral economics shows how decisions are influenced by external factors and cognitive biases, such as “anchoring” and “loss aversion.” Sellars contrasts these frameworks to highlight the tension and complementarity between philosophical reflection and scientific inquiry (Sellars 1963: 19).
3Physicalism has clearly become the dominant view in contemporary philosophy. Given its significance in philosophical debates, it is necessary to distinguish between different forms of physicalism in a more systematic and detailed way. Building on Sellars’ distinction between the scientific image and the common sense image, we can divide physicalism into two types: scientific physicalism and common sense physicalism. A fundamental question we face today is whether the explanation of conscious experience should rely solely on the methods of the natural sciences, or whether it should also involve a systematic reflection on human cognition. Scientific physicalism holds that all conscious experience can be explained purely through scientific methods.
4In contrast, common sense physicalism suggests that both scientific understanding and everyday cognition should work together to explain conscious experience. Common sense physicalism holds that, at a fundamental level, the world is made up of human beings and their macroscopic physical surroundings. While this view is less accepted in mainstream science compared to scientific physicalism and has faced some criticism, it offers a unique perspective that deserves serious consideration. This approach emphasizes everyday human experiences and perceptions, focusing on how large-scale physical phenomena interact with individual perceptions and social and cultural contexts.
5The relationship between scientific physicalism and common sense physicalism can be understood through a metaphor in the Odyssey, where Odysseus faces a choice between two dangers: Scylla and Charybdis. Scylla is a six-headed monster that devours ships and sailors, while Charybdis creates a whirlpool that sinks ships (Homer 1945: 439-63).
6Like Odysseus, who had to choose between two perilous paths, we are often faced with weighing the pros and cons when choosing between two dangers. Scientific physicalism is widely accepted and considered a well-established path, while common sense physicalism can be seen as a less-traveled one. Philosophers who embrace common sense physicalism often find themselves in a difficult position: scientists criticize it for not fully adhering to a scientific explanatory framework, while humanists argue that it leans too heavily on science, neglecting more human-centered interpretations. This seemingly eclectic stance may spark a range of philosophical debates and reactions, making it a position that deserves further study and exploration.
7Common sense physicalism and pragmatism share a standpoint of experiential primacy in philosophical methodology. Both advocate for the instrumental nature of theory, oppose extreme reductionism, and emphasize a practice-oriented approach. This provides a fresh perspective for analyzing whether medical materialism and scientific physicalism can fully explain religious experience. In contemporary philosophical discussions, religious experience, as a core issue, is often placed within the research scope of scientific physicalism and medical materialism. However, whether these two positions can truly explain religious experience, especially its intrinsic qualitative aspects (qualia), remains a pressing and unresolved debate. The intersection of common sense physicalism and pragmatism provides a mediating framework, one that not only acknowledges the explanatory value of science in understanding religious experience but also emphasizes the diversity and complexity of experience. This suggests that relying solely on scientific explanations may not fully capture the deeper implications of religious experience.
8The first section of the paper explored the differences between common sense physicalism and scientific physicalism, introducing the central issue of whether medical materialism and scientific physicalism could explain religious experience. The second section discusses the relationship between religious experience and medical materialism, concluding that if the qualitative aspect of religious experience cannot be explained by science, medical materialism cannot fully explain religious experience. The third section will analyze William James’s critique and reflection on medical materialism, pointing out that James’s pragmatism, similar to common sense physicalism, opposes medical materialism. This section will focus on James’s four arguments: Begging the Question, the Argument from Equivalence, the Argument from Explanation, and the Argument from Origin. The fourth section will discuss responses to James’s critique of medical materialism, particularly within the field of psychology, from the perspective of common sense physicalism. The fifth section will conclude the paper by acknowledging that, while not denying the contributions of religious neuroscience and medical materialism in their respective fields, these studies only provide necessary knowledge, not sufficient knowledge, about religious experience. The task of philosophy is not only to reveal the value and limitations of medical materialism but also to continue to expand at the boundaries of neuroscientific cognition, gradually forming a comprehensive perspective that integrates philosophy and science in order to understand and know the world more fully.
9Religious experience refers to the personal or collective experience of individuals in a specific religious or spiritual context. It is often described as a state of connection with divine, transcendent forces, supernatural powers, or absolute truth. William James captures the essence of religious experience by describing the subject in the following way:
Were we to limit our view to it, we should have to define religion as an external art, the art of winning the favor of the gods. In the more personal branch of religion it is on the contrary the inner dispositions of man himself which form the centre of interest, his conscience, his deserts, his helplessness, his incompleteness. And although the favor of the God, as forfeited or gained, is still an essential feature of the story, and theology plays a vital part therein, yet the acts to which this sort of religion prompts are personal not ritual acts, the individual transacts the business by himself alone, and the ecclesiastical organization, with its priests and sacraments and other go-betweens, sinks to an altogether secondary place. The relation goes direct from heart to heart, from soul to soul, between man and his maker. (James 1901/1928: 29)
10James argues that the core of private religious experience is found in the mystical state of consciousness. Religious experience is typically seen as something beyond ordinary sensory experiences, marked by significant emotional, perceptual, or cognitive shifts. It is an inner experience of religious or supernatural significance, often felt in specific situations. This experience is usually accompanied by a deep emotional and perceptual response to the divine, transcendent, spiritual, or ultimate reality. Because religious experience is closely tied to internal mental activities – such as cognition, emotion, and consciousness – it is highly personal and individualized, making it difficult to measure or observe directly through external or scientific methods.
11William James believed that the fundamental point of all religions lies in personal mystical experience, and he uses the term “mysticism” in a very broad sense. He describes it in the following way:
One may say truly, I think, that personal religious experience has its root and centre in mystical states of consciousness […] The words “mysticism” and “mystical” are often used as terms of mere reproach, to throw at any opinion which we regard as vague and vast and sentimental, and without a base in either facts or logic. For some writers a “mystic” is any person who believes in thought-transference, or spirit-return. Employed in this way the word has little value: there are too many less ambiguous synonyms. (Ibid.: 379-80)
12James argues that the practical use of the term “mystical experience” is limited due to the many synonyms that express a similar ambiguity. To clarify its academic value, he proposes defining it by four key characteristics: ineffability, noetic quality, transiency, and passivity (ibid.: 380-2). Ineffability means that the content of mystical experiences cannot be adequately expressed through language; rather, it can be directly experienced, and much like emotions cannot be fully communicated to others. Noetic quality indicates that although mystical experiences resemble emotional states, they are perceived as cognitive, providing insights and revelations beyond rational understanding. Transiency refers to the short-lived nature of mystical experiences, typically lasting no more than an hour or two. However, they often leave a lasting impression of profound significance when recalled. Passivity reflects the sense of surrender during mystical experiences, where the individual feels as though they are being acted upon by an external force, losing active control but experiencing profound inner transformation. These four characteristics focus primarily on the structural aspects of mystical experiences rather than their content or emotional expression (ibid.).
- 1 Chen Xianzhang (1428-1500), a significant thinker, philosopher, educator, calligrapher, and poet du (...)
- 2 All translations and quotations regarding Chen Xianzhang’s philosophical thought in this paper are (...)
- 3 The concept of “heart” (cor) in Saint Augustine refers to the moral and spiritual center, while in (...)
13In traditional Chinese Confucian philosophy, particularly during the Song and Ming dynasties, mystical experience is often described phenomenologically. While Song and Ming Confucianism includes mystical elements, mysticism was not the dominant tradition within Confucianism – rationalism consistently held that role (Lai Chen 2006: 362). What would later be termed “Song and Ming philosophy,” which evolved from Ming dynasty Confucianism, offered a well-developed understanding of mystical experience. Chen Xianzhang,1 for instance, emphasized achieving inner experience through meditation, a common Confucian practice. The core concept here is the “disclosure of the heart’s form 心体呈露.”2 This term can be challenging to explain to those unfamiliar with it, but it generally refers to an “inner mystical experience” involving pure consciousness (Xianzhang Chen 2008a: 234). The “heart’s form 心体”3 refers to the original, unaltered state of the heart. Song and Ming Confucians practiced meditation to block out distracting thoughts and observe the image (qixiang 气象) that existed before thoughts emerged. The purpose of this practice was to reveal the proper “heart’s form 心体” (Lai Chen 2006: 363).
14Chen Xianzhang urged people to attain the experience of “disclosure of the heart’s form” through meditation. However, he also introduced another form of mystical experience:
- 4 The use of the term “universe” is a complex issue. In ancient Chinese philosophy, the concept of th (...)
Heaven and Earth – I establish them; the myriad things – I give rise to them. The entire universe 宇宙4 is in me. If one can get hold of this handle (babing 把柄), what else is there left to do? The past and the present, the four directions 四方 and what is above and below are all strung together as if through a buttonhole, they are all gathered together. (Xianzhang Chen 2008b: 298)
15Chen Xianzhang described a profound mystical experience in which the self merges with universe 宇宙: “Heaven and Earth – I establish them; the myriad things – I give rise to them. The entire universe 宇宙 is in me.” This refers to a mystical state where the individual experiences a unity between the self and universe 宇宙. He further elaborates on this experience, “The past and the present, the four directions 四方, and what is above and below are all strung together as if through a buttonhole, they are all gathered together,” which expresses a sense of transcending time itself. In this state, the individual’s consciousness surpasses the physical limitations of space and time, achieving a comprehensive understanding and control of the entire universe 宇宙 across time and space. This experience is not merely an observation of universe 宇宙 but also a deep awareness of one’s unique place within it, and reflects a profound unity between the self and universe 宇宙. However, the term “universe 宇宙” in this context should not be understood as “universe” in the sense of modern physics. Instead, it requires a distinct interpretation that reflects this broader, philosophical understanding of universe (yuzhou) 宇宙 and self:
The term “yu宇” refers to the existence of four directions 四方 – above, below, and the four cardinal points – yet these directions are boundless and without limit. The term “zhou 宙” signifies the continuity of past and present, but this continuity of time extends infinitely, without end. (Xiang Guo 2011: 419)
16Chen Xianzhang refers to the acquisition of this mystical experience as “babing 把柄,” suggesting that mastering this practice is the key to accessing the essence of universe 宇宙 and gaining insight into all things in heaven and earth. This “handle” represents not only the elevation of an individual’s spiritual realm but also a means of deepening inner cultivation and mindfulness. For Chen Xianzhang, “babing 把柄” symbolizes his profound understanding of the connection between the individual mind and universe 宇宙 within his teleological framework.
17Li Zehou once discussed religious experience and proposed replacing religion with aesthetic education, essentially substituting aesthetic experience for religious experience. Notably, Li Zehou distinguished between sensory mystical experience and rational mystical experience. He classified religious and aesthetic mystical experiences as sensory, while describing the realm of Heaven and Earth and the philosophical mysteries of Chinese philosophers as rational. From this distinction, religious experience is considered a form of sensory mystical experience. In Li Zehou’s view, “sensory mysticism” or mystical experience can be explained and interpreted by future brain science, and even replicated. Its “divine” nature would therefore be difficult to preserve and would cease to be mystical. However, “rational mysticism” is not the object of brain science or psychology and cannot be answered by them (Zehou Li 2019: 187).
18Here, Li Zehou adopts a scientistic attitude toward religious experience, which is more optimistic than the view advocated in this paper. This paper argues that even sensory mystical experiences cannot be fully explained through so-called medical methods and medical materialism. This will be further elaborated in Section 3, where William James’ rebuttal of medical materialism is discussed.
19In The Varieties of Religious Experience, William James critically examines medical materialism, which asserts that religious experiences are merely the product of the nervous system and can be fully explained through materialistic means. James rejects this view, arguing that it is arbitrary to reduce religious experiences to the nervous system while overlooking similar possibilities for other conscious experiences, such as scientific reasoning or doubt. He further contends that if all states of consciousness are seen as mere results of bodily conditions disconnected from external reality, then this reductive explanation becomes equally questionable. James suggests that religious and mystical experiences should be evaluated like any other human experiences – based on their “direct glory,” “philosophical justification,” and “moral assistance” – rather than relying exclusively on neurobiological explanations (James 1901/1928: 118-23).
20Medical materialism argues that the psychological states of religious believers can be explained through their bodies, especially the physiological mechanisms of the brain. More specifically, it posits that neuroscience can provide a sufficient and necessary explanation for religious experiences. James pointed out that:
Medical materialism finishes up Saint Paul by calling his vision on the road to Damascus a discharging lesion of the occipital cortex, he being an epileptic. It snuffs out Saint Teresa as an hysteric, Saint Francis of Assisi as an hereditary degenerate. George Fox’s discontent with the shams of his age, and his pining for spiritual veracity, it treats as a symptom of a disordered colon. Carlyle’s organ-tones of misery it accounts for by a gastro-duodenal catarrh. All such mental over-tensions, it says, are, when you come to the bottom of the matter, mere affairs of diathesis (auto-intoxications most probably), due to the perverted action of various glands which physiology will yet discover. (Ibid.: 13)
21William James argued that medical materialism seems to be a fitting term for a rather simplistic system of thought regarding the issue at hand. This position shares notable similarities with contemporary reductive physicalism in its approach to explaining conscious phenomena, both attempting to fully reduce and explain human mental and conscious experiences through physical and physiological processes. Specifically, medical materialism holds that religious experiences are merely products of brain activity and can therefore be interpreted through neuroscientific research. This view represents the contemporary version of neuroscience applied to religious experience.
22However, William James clearly opposed the path of medical materialism that uses neurological research to study religious experience, arguing that this approach is overly simplistic and limited. While neuroscience has become an important tool for understanding religious experience in modern times, James believed it could not provide a sufficient explanation. In his view, religious experience has profound subjectivity and complexity, and simply examining these phenomena from the perspective of neuroscience not only overlooks the uniqueness of religious experiences but also fails to capture their full meaning and essence.
23James took a clear stance against medical materialism and criticized it through a series of arguments. According to this analysis, he presented at least four main arguments: Begging the Question, the Argument from Equivalence, the Argument from Explanation, and the Argument from Origin. These arguments not only highlight the inherent deficiencies of medical materialism but also emphasize the limitations it faces in explaining religious experience.
24First, regarding the mind-body problem, there is a dilemma of Begging the Question. As James pointed out:
To plead the organic causation of a religious state of mind, then, in refutation of its claim to possess superior spiritual value, is quite illogical and arbitrary, unless one have already worked out in advance some psycho-physical theory connecting spiritual values in general with determinate sorts of physiological change. Otherwise none of our thoughts and feelings, not even our scientific doctrines, not even our dis-beliefs, could retain any value as revelations of the truth, for every one of them without exception flows from the state of their possessor’s body at the time. (Ibid.: 14)
25The key issue here is that, to date, we have not found a universally accepted or irrefutable philosophical theory of the mind-body relationship, nor a single, widely accepted neuroscientific theory of consciousness. In the field of philosophy of mind, positions such as physicalism and dualism are still subject to intense debate. Furthermore, in neuroscience, hypotheses like the Global Workspace Theory and the Integrated Information Theory are still competing with each other, without forming a unified theoretical framework (Storm et al. 2024). As a result, it is not possible to reduce religious experiences to underlying physiological causes based on any specific theory.
26Within the framework of scientific physicalism, the study of religious phenomena is primarily divided into two paths: One is the evolutionary biology of religion, which focuses on the adaptive functions of religious thought and behavior through natural selection, as well as their cultural universality (Boyer & Bergstrom 2008; Achtner 2009). The other is the genetics of religion, which explores the relationship between genes and religious behavior while reflecting on ethical issues such as genetic engineering through the dialogue between science and religion (Nelson 1994: 193-200; Simmons 1995: 255-6). But, this lack of consensus weakens the defense of the so-called “neuroscience of religion” approach itself. While some scholars may argue that, despite the absence of a single correct reductionist theory, we can still perform some degree of reduction, such reduction does not constitute a necessary condition for conscious experience. For example, Daniel Dennett’s “Multiple Drafts Model” proposes that consciousness is a narrative stream constructed by multiple parallel and dynamic editorial processes in the brain. In this model, information is continuously revised and integrated through the nervous system to form experience, and the emergence of consciousness does not depend on a fixed point in time or the activation of specific regions (Dennett 1991: 111-3); at best, it can only be considered a supporting condition.
27Next, James’ Argument from Equivalence seeks to reveal the symmetry in reasoning between religious belief and non-belief. James points out:
It is needless to say that medical materialism draws in point of fact no such sweeping skeptical conclusion. It is sure, just as every simple man is sure, that some states of mind are inwardly superior to others, and reveal to us more truth, and in this it simply makes use of an ordinary spiritual judgment. It has no physiological theory of the production of these its favorite states, by which it may accredit them; and its attempt to discredit the states which it dislikes, by vaguely associating them with nerves and liver, and connecting them with names connoting bodily affliction, is altogether illogical and inconsistent. (James 1901/1928: 14-5)
28James uses this passage to reveal the inherent contradiction in medical materialism’s approach to mental states. While medical materialism advocates for the physiological basis of mental states, it paradoxically treats certain mental states (such as pleasure or revelation) as higher truths, while easily attributing others (such as certain religious or emotional experiences) to physiological or pathological reactions, despite lacking sufficient theoretical support. This practice of linking disliked mental states to bodily diseases is clearly irrational and represents a logically inconsistent form of reasoning.
29Through this critique, James emphasizes the relativity between the two positions – whether supporting the superiority of certain mental states or attributing them to physiological pathology – both depend on a general, unverified “mental judgment.” Medical materialism fails to provide a sound physiological theory to support its preference for certain mental states; it merely relies on a common mental judgment to determine certain experiences as “real” or “valuable.” This resonates with the Argument from Equivalence: both positions (belief and non-belief, liking or disliking certain mental states) are based on beliefs that lack rigorous justification. Therefore, neither side can claim to have a clear, transcendent rational foundation and might further seek independent, convincing evidence.
30This line of reasoning in the Argument from Equivalence has broad applicability in philosophical debates, especially when opposing positions are involved. For example, if a piece of evidence can equally support Position A and Position B, the weight of the evidence for both positions is equivalent, and thus neither position can claim superiority based solely on that evidence. In such cases, the debate reaches a deadlock of evidential symmetry. To break this impasse, each side might provide independent and clear evidence to support its specific position, avoiding logical insufficiency.
31Then, James’ “Argument from Explanation” addresses the standards we rely on when evaluating certain mental states or psychological conditions. He states that:
When we think certain states of mind superior to others, is it ever because of what we know concerning their organic antecedents? No! it is always for two entirely different reasons. It is either because we take an immediate delight in them; or else it is because we believe them to bring us good consequential fruits for life […] When we praise the thoughts which health brings, health’s peculiar chemical metabolisms have nothing to do with determining our judgment. We know in fact almost nothing about these metabolisms. It is the character of inner happiness in the thoughts which stamps them as good, or else their consistency with our other opinions and their serviceability for our needs, which make them pass for true in our esteem. (James 1928: 15)
32He points out that when we consider certain mental states to be superior to others, this judgment is not based on an understanding of the physiological causes of these states, but rather on two completely different reasons: first, because we directly derive pleasure from these mental states; and second, because we believe these states will lead to positive life outcomes. James further emphasizes in The Varieties of Religious Experience that this intuitive evaluation and understanding of mental states cannot be reduced to microscopic physiological causes but should appeal to reasons at a level consistent with the mental states themselves.
33This view reflects James’ hierarchical understanding of mental states: when we explore the nature of health or psychological states, we do not rely on minute physiological processes or chemical reactions, but rather on factors that directly affect our everyday experiences. For example, when we praise the thoughts brought about by good health, we do not consider the physiological metabolism or chemical mechanisms of health, and we are often virtually ignorant of these mechanisms. On the contrary, we regard the thoughts triggered by health as good precisely because they bring us inner pleasure; we consider them to be true because they align with our other beliefs and opinions, or because they effectively meet our life’s needs. This understanding highlights the role of intuition and value judgments in human experience, which often occur directly without the need for in-depth analysis of their physiological foundations.
34This critique can be extended to the understanding of religious experience. Religious belief and experience often involve complex emotional and psychological states, which cannot be fully explained merely from the perspective of neurobiology or chemical metabolism. While neuroscience can provide us with a detailed picture of brain activity and physiological responses, these biological descriptions cannot fully capture the deeper meaning and personal value inherent in religious experiences. The intrinsic pleasure of religious experience, its alignment with other belief systems, and its positive impact on personal life and culture are key factors in our understanding of these experiences. Therefore, the explanations provided by religious neuroscience cannot fully replace the intuitive understanding we rely on in our everyday lives.
35Lastly, there is the Argument from Origin. William James (1901/1928: 18-9) states:
Dogmatic philosophies have sought for tests for truth which might dispense us from appealing to the future. Some direct mark, by noting which we can be protected immediately and absolutely, now and forever, against all mistake – such has been the darling dream of philosophic dogmatists. It is clear that the origin of the truth would be an admirable criterion of this sort, if only the various origins could be discriminated from one another from this point of view, and the history of dogmatic opinion shows that origin has always been a favorite test. Origin in immediate intuition; origin in pontifical authority; origin in supernatural revelation, as by vision, hearing, or unaccountable impression; origin in direct possession by a higher spirit, expressing itself in prophecy and warning; origin in automatic utterance generally, – these origins have been stock warrants for the truth of one opinion after another which we find represented in religious history.
36In James’ view, both the religious adherents to the history of religion and medical materialists appeal to origins. Origins may be rooted in intuition, the authority of the Pope, supernatural revelation, or the body and brain. They all share a basic conceptual framework. However, when it comes to explaining religious experience, we cannot simply appeal to origins. As discussed earlier, there is a distinction between how something comes into being and what it is in itself. Religious neuroscience confuses the context of discovery with the context of justification. We need to understand religious explanations within the context of justification. The core issue is that science can only tell us how something develops, but it cannot fundamentally tell us why it is so, which presents a fundamental difficulty in the neuroscientific explanation approach.
37In these four arguments, Begging the Question and the Argument from Equivalence fall into one category. Since we do not have a single unified theory of neuroscience, we are trapped in a cycle of argument, and both reductionist and non-reductionist explanations can be defended. However, suppose that one day we acquire a single theory of neuroscience; in that case, these two arguments could be refuted. The Argument from Explanation and the Argument from Origin are different. Even if we have a single theory of neuroscience, we cannot dismiss these two arguments. The reason is that our standards of explanation are independent and need to be understood at the same level of mental activity, rather than being entirely reduced to the microscopic level. It is also possible to take a step back: the microscopic level indeed provides some necessary explanations for macro-level mental activities, but it cannot fully explain human psychological activities or religious experiences.
38Explanation has two dimensions: one is the synchronic explanation from the microscopic to the macroscopic, and the other is the diachronic explanation from the macroscopic to the macroscopic. To fully explain religious experience, both dimensions are necessary. Wittgensteinianism might argue that only the diachronic explanation is needed, and that neuroscience cannot provide any explanation for religious experience at all. We distance ourselves from this position. However, we do not offer an argument to demonstrate why both explanatory dimensions are required, but simply appeal to general explanatory intuition. This touches on how we approach the question of explanation: What role do scientific explanations, metaphysical explanations, narrative explanations, and other forms of explanation play in our understanding of things? A systematic discussion of this topic is needed, but it will not be elaborated here.
39There is a fundamental consistency between William James’s critique of medical materialism and the common sense physicalist’s critique of scientific physicalism. While common sense physicalists deny the existence of God, they do not deny the reality of religious experience. As Jeffrey Poland notes in Physicalism: The Philosophical Foundations:
Physicalism implies that there are no supernatural gods or other beings and that the claims of many religious texts are literally false. But physicalists can make such judgements while not necessarily condemning the religious beliefs and practices involved. Literal truth is by no means always what is important in a given context, and physicalists, like everyone else, must honour that fact of life. (Poland 1994: 357)
40Acknowledging that the mental level has its independent ontological status does not necessarily contradict the core principles of physicalism. Physicalists can maintain that there is a necessary connection between the mental and physical levels while also recognizing that this connection is non-reducible. This means that while the mental level depends on the physical, it does not have to be reduced to purely physical processes. In practice, the mental level can be treated as fundamental without needing to explain its role and nature through reductionism. This approach encourages a deeper consideration of the “ontology of psychology” and explores how psychology can exist independently from the hierarchical framework of physics. The psychologist Li Qiwei’s discussion of the relationship between psychology and physiology aligns with this view, suggesting that psychology can exist independently of physics and possess its explanatory power – an idea that resonates with common sense physicalism:
A significant issue often goes unnoticed: the study of the brain and nerves is not entirely “conjoined” with psychology, though it can be seen as a “brother” of psychology. It is not surprising that for every psychological activity, there are corresponding physiological activities. These physiological aspects are meant to support psychological research, not replace or overshadow it. (Qiwei Li 2019: 2)
41Psychological research must treat the psyche as its primary ontology, using physiological methods as auxiliary tools to investigate psychological phenomena. Similarly, the philosophy of mind should consider mental phenomena as its core focus, using the methods of natural science as supplementary approaches. However, Li Qiwei places significant emphasis on the reductionist method:
Reductionism is “sewage,” but there are “children” in the “sewage” (there is valuable empirical research data amid reductionist discourse). To keep the child, replace the “sewage” with “freshwater” (a non-reductionist interpretation of the data). Without this shift, the significance of current neuroscientific research paradigms, which are highly regarded in psychology, would be significantly diminished. Some might criticize this approach as a form of disguised reductionism, but it is more appropriately described as exploring the “neural correlates of the psyche.” Reduction should focus on the level of psychological mechanisms, not the specific content of psychological experience. For example, when someone loses money and becomes upset, corresponding changes occur in the brain. These changes are likely universal across individuals, but they cannot be reduced to specific details, like whether the loss was in CNY or USD or whether the amount was 100 or 200 units. When it comes to the specific content of thought, absolute, one-to-one physiological-psychological reduction is impossible. Moreover, no current or future brain research programs, whether domestically or internationally, will fully explain higher cognitive functions – such as learning, memory, and thinking – solely on their neural basis. (Ibid.: 3)
42Psychology should focus on studying the processes and mechanisms of mental activity, and in this sense, neuroscientific research is necessary, but more is needed. When it comes to the neuroscientific study of consciousness, Chen Jiaying highlights the following:
Neuroscience expands into the field of consciousness not to dominate the area but to advance its understanding. In doing so, it must take into account the various characteristics of consciousness – much like how geologists studying the foundation of a building need to understand many aspects of the building itself. (Jiaying Chen 2021)
43Foundations are essential for construction – without them, no building can be erected. Similarly, the neuroscientific study of consciousness is necessary to provide a basis for a comprehensive understanding of consciousness. However, just as architects focus on designing buildings rather than foundations, neuroscientific inquiry into consciousness is meant to support a broader understanding, not to focus solely on neural foundations. The purpose of studying foundations is to construct buildings, not just to understand the foundations themselves. To fully understand a building, one might also consider its function – whether it is meant for housing or offices or whether its style is Chinese or European. These aspects are not fully grasped by those focused solely on the structural base.
44Common sense physicalism is known by various similar names, such as “physicalism within self,” “macro-physicalism,” and “object-based physicalism.” However, the primary position can be summarized as follows:
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Fundamental Physical Existence: Human beings and the objects around them are, at their core, physical entities.
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Materialist View of Consciousness: Every conscious activity is accompanied by brain activity, and in this sense, we are materialists. It is a matter of basic common sense that no conscious activity occurs without corresponding brain activity.
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Non-Reductive Relationship: Conscious activity does not have a simple one-to-one correspondence with brain activity, meaning that while connected, consciousness cannot be fully reduced to brain processes.
45Some conscious activities can be linked to specific neural correlates of consciousness (NCC). For instance, scholars studying the neuroscience of religion have found significant differences in the degree of religiosity in groups of patients. Their research showed that religiosity was significantly correlated with reduced right hippocampal volume, but not amygdala volume, in both groups (McNamara 2009: 92-4). In such cases, the connection between conscious experience and neural activity is evident and unquestionable. However, not all conscious activities can be mapped to exact neural correlates, as the sources of conscious experience are complex and varied. These involve the external world, subjective feelings, and abstract thought. For example, it is difficult to pinpoint precise neural correlates when someone is deeply immersed in creating art or appreciating poetry. Such highly abstract conscious activities cannot be easily explained through neuroscientific methods. Another technology that has gained attention in recent years is the brain-computer interface. It allows paralyzed individuals to control external devices, like robotic hands or computers, using neural signals from their minds. This technology demonstrates how specific neuronal firing patterns can be decoded to represent particular intentions. However, even with advances in this technology, it remains challenging to fully capture the complex conscious activities of the brain through neurotechnology alone.
46We believe that it remains impossible to restore the brain’s thought activity through neural techniques fully. The reason is that certain representations of consciousness are not manifested at the neuronal level in ways that are fully detectable by neurotechnologies, even as these technologies continue to advance. Even if, in principle, it became possible to detect all neural activity in the brain, this would still be insufficient to explain consciousness fully. As William James pointed out, explanations occur at the level of consciousness itself. Simply relying on descriptions of neural activity or chemical reactions cannot capture the true nature of conscious experience. Thus, while neuroscience can reveal some of the mechanisms behind consciousness, it cannot fully address the more profound, fundamental issues of consciousness.
47From a common sense physicalist perspective, while cognitive and neuroscientific approaches to the study of religion cannot fully explain religious experience, they provide necessary insights for understanding it. However, what ideas should be used to explain religious experience more comprehensively? William James suggests that religious experience should be explained at the same level as consciousness itself – that is, through everyday perception and direct experience. This approach warrants further exploration: What types of everyday perceptions or experiences can effectively explain religious experience and the phenomenon of consciousness?
48To answer this, we might distinguish between two types of common sense. The first is personal, fragmented, and unreflective, which is often unreliable and unsuitable as a foundation for explanation. The second type, however, is systematic common sense, refined by science, philosophy, and the experiences of both self and others. This more sophisticated common sense not only encompasses systematic human cognition but also transcends any single method of perceiving conscious experience (e.g., purely scientific interpretations).
49Systematic common sense integrates various cognitive outcomes and is not constrained by any one disciplinary perspective. Exploring consciousness and religious experience through everyday perception, using this form of common sense opens up new ways of thinking about the study of consciousness. This approach avoids the limitations of reducing consciousness solely to neuroscientific explanations and allows for a more prosperous, multilayered understanding of conscious experience. By incorporating diverse elements of common sense and experience, this perspective offers a more comprehensive explanation of both consciousness and religious experience, particularly when investigating human perceptual and cognitive frameworks.
50Only with this balanced perspective can we fully grasp the significance of religious neuroscience research in exploring religious experience. On the one hand, we engage with cutting-edge advances in the neuroscience of religion and immerse ourselves in the details of this research, striving for a comprehensive understanding of the field. On the other hand, it is crucial to recognize that while these studies provide a necessary intellectual foundation for exploring religious experience, more is needed to offer a complete explanation.
51The role of philosophy is not only to highlight the value of neuroscientific studies of religion but also to point out its limitations. As the neuroscience of religion reaches the limits of its explanatory power, philosophy should continue to foster more profound discussions about religious experience, extending the exploration where neuroscience cannot entirely go.
52Only by properly recognizing the relationship between science and religion and between scientific and common sense understanding can we fully grasp the significance of neuroscience research on religion for human understanding. To achieve the most profound insight into the technical and theoretical implications of this research, we should carefully engage with the cutting-edge advances and details of the neuroscience of religion.
53By examining the intricate relationship between neural activity and religious experience, neuroscience can shed light on how specific neural mechanisms contribute to the production, perception, and response to religious experience. However, it is crucial to acknowledge that while the neuroscience of religion provides valuable knowledge, its insights are limited to a certain level of reductive explanation. This means that it needs to offer a complete understanding of the complexity of religious experience.
54The task of philosophy is not only to highlight the unique value of the neuroscientific study of religion but also to reflect on and critique its methodological and explanatory limitations. While neuroscience can provide insights into the physiological conditions under which religious experiences occur by observing brain activity, the nature of religious experience goes beyond being merely a biological phenomenon. It encompasses more complex existential, epistemological, and ethical dimensions. Therefore, philosophy continues to explore areas that neuroscience has yet to address, proposing a more comprehensive and integrated understanding of religious experience. By doing so, philosophy can enrich the dialogue concerning these issues and offer deeper insights into the multifaceted nature of religious experience.
55This task requires philosophers to build upon the knowledge provided by the neuroscience of religion, delving deeply into the nature of religious experience – its inherent subjectivity, transcendence, and emotional significance. Philosophy should not only explain and extend the insights from neuroscience but also explore religious experience within its broader cultural, historical, and social contexts. It is evident that common sense physicalism and pragmatism share a focus on the importance of experience, an instrumental understanding of theory, opposition to extreme reductionism, and an orientation toward solving practical problems. Common sense physicalism emphasizes the integration of science and common sense, while pragmatism prioritizes the practical utility of theories. Although their starting points differ, they share significant common ground in rejecting abstract metaphysics, highlighting the complexity of experience, and adopting a practice-centered approach. This connection provides a framework for philosophical inquiry that integrates empiricism and pragmatism. By doing so, philosophy can address the complex supernatural, moral, and existential questions embedded in religious experience. This interdisciplinary integration allows for a more complete understanding that goes beyond a purely biological perspective, offering a richer and more nuanced view of religious phenomena.