Halligan and Oakley’s Species-Enhancing Epiphenomenalism

Psychologists Peter Halligan and David Oakley propose that consciousness is an epiphenomenon that evolved from underlying brain physiology. They define consciousness as “embodied subjective awareness including meta-cognition” and epiphenomenon as “inner what-it-is-like feelings without causal powers.” They argue that much of the mind’s cognitive architecture evolved to service sociality—the tendency of groups and people as persons to develop social links and live in communities—a key survival strategy for human growth, well-being, and species reproduction. Adopting this social evolutionary account, they propose that subjective awareness is not causally efficacious but rather a brain-generated accompaniment of selective neuro-cognitive outputs designed to facilitate collective social communication and social harmony through the cultural transmission of beliefs, feelings, ideas, and behaviors (Halligan & Oakley, 2024, 2015, 2017, 2021).

Intuitive Accounts and Their Influence

While the term consciousness can mean different things to different people, nothing appears more real than the intimate experience of subjective awareness and its powerful feelings of self-directed control (Halligan & Oakley, 2015, 2017). As such, most people know what “consciousness” is and what it does precisely because they experience it every day. Given these compelling, self-evident, pre-theoretical intuitions, explaining the nature of consciousness never really required formal scientific or philosophical explanation until the late development of psychology as a science at the end of the 19th century.

Shtulman (2022a) claims that intuitive accounts have their origins in evolution, where innate expectations form the foundations of intuitive theory-building, shaping how we perceive, interact with, and explain the world around us. Unlike scientific accounts, first-person intuitive accounts, or lay theories, shaped by a lifetime of subjective awareness, provide an effortless, immediate explanation rarely questioned or requiring justification. The self-evidential nature of these intuitive accounts—which locate consciousness firmly in the driver’s seat—helps explain why formal studies of consciousness were relegated to the margins of mainstream psychology until the late 20th century (Seth, 2018).

One of the most powerful intuitive beliefs that influence the way people perceive and explain subjective awareness is mind-body dualism, a pervasive conviction that the private mental world (thoughts, memories, intentions, feelings) are qualitatively distinct from and cannot be fully explained by the operation of biological brains (Barrett et al., 2021). Acceptance of this mind-body distinction, found in most human cultures and young children, has in turn provided for the intuitive notion of mental causation—a belief that receives daily confirmation by the fact that it underpins the existence and operation of most liberal political systems of government, education, health care, and criminal justice.

Intuitive accounts remain persuasive and enduring precisely because of their everyday endorsement, where individuals as social players are held accountable and responsible for their behaviors, actions, and speech. Publicly endorsed social realities, such as democracy, human rights, universal suffrage, citizenship, equality, equity, and disability, are all predicated on the assumption that persons possess some form of executive embodied agentive capacity (e.g., free will) used to regulate group/social governance and justice. Where societal governance collectively creates social constructs (e.g., human rights, laws, nation boundaries), as “real” then, these social realities have a material impact on the person and the way society is collectively organized and governed (Feldman Barrett, 2020).

Given the need for scientific accounts of human psychology to accommodate this intuitively informed compelling role for subjective awareness, it is not surprising that many accounts take and incorporate the not unreasonable, intuitive belief that outputs from our mental states, thoughts, intentions, beliefs, and feelings somehow cause and control behaviors (Halligan & Oakley, 2021).

While helpful when explaining many everyday experiences, intuitive or common-sense accounts can lead to scientific misconceptions (Shtulman, 2022b). The challenge for any materialist, scientific account of human psychology is to reconcile these compelling pre-theoretical intuitive accounts that argue for personal liberty and responsibility with the known biologically determined neuroscientific evidence. Evidence from cognitive development suggests that ill-informed intuitive beliefs coexist in many areas of science, potentially delaying and obstructing the acceptance of scientific accounts (Shtulman, 2022a). Such accounts are historically entrenched and culturally widespread, making them inerasable and resistant to counter evidence.

Epiphenomenal Model and Social Function

While the human mind can be described as comprising both conscious and nonconscious aspects, both ultimately depend on neural processes in the brain. Persuaded by the growing evidence from cognitive neuroscience over the past three decades, Halligan and Oakley consider that the psychological outputs and executive functions typically attributed to subjective awareness are carried out competently backstage by a myriad of fast, efficient non-conscious brain systems. Contrary to intuitive accounts, Halligan and Oakley consider subjective awareness to be a brain-generated accompaniment that sits alongside psychological outputs derived from the non-conscious functioning of the brain’s evolved neurocognitive architecture (Halligan & Oakley, 2017, 2021).

According to their account, selective psychological outputs from unconscious brain processes (such as thoughts, sensations, intentions, beliefs, memories, emotions) are internally broadcast to form the contents of conscious experience, a form of self-referential personal narrative. This continuously updated personal narrative, a form of selective “internal broadcasting” of outputs from non-conscious brain systems, is not, however, directed or influenced in any way by the experience of consciousness itself. Both the contents and experience of consciousness are epiphenomenal end products of unconscious processes themselves serving the powerful evolutionary function of enabling individuals to communicate (externally broadcast) the contents of their internal broadcasting to other individuals.

Taking a social evolutionary approach, Halligan and Oakley aver that subjective awareness is a brain-generated mental representation, part of a more extensive evolved biological hardware that lacks the neuro-cognitive capacity to causally influence other psychological processes or behaviors (Halligan & Oakley, 2024).

Halligan and Oakley claim that subjective awareness evolved to serve the needs of humans as social beings rather than exclusively for the benefit of us as biological organisms. As such, the mental architecture of the mind is strongly adapted for the exchange and reception of information, ideas, and feelings. As the German philosopher Friedrich Nietzsche noted, “Consciousness is really only a net of communication between human beings… consciousness does not really belong to man’s individual existence but rather to his social or herd nature” (Nietzsche, 1974).

The claim that subjective awareness is without causal influence is not to deny the reality or value of subjective experience for us as individuals. While it feels counterintuitive to attribute agency and personal accountability to a biological assembly of nerve cells, it makes more sense to attribute highly valued social realities such as free will, justice, democracy, and morality to individuals considered as persons living within a social community.

Achieving a more scientific explanation of subjective awareness as part of a comprehensive account of human psychology means accepting that biology and culture work collectively to shape how brains evolve and that subjective awareness, although experienced as phenomenologically real, comprises one part of the brain’s much larger mental architecture designed to facilitate species' survival and well-being (Frith, 2007).