epiphenomenalism - Background, Some critical responses, Arguments for, Arguments against

A theory which maintains that mental phenomena are distinct from and caused by physical phenomena. They are the incidental effects of physical events, and so exert no causal influence on the physical world. Thus T H Huxley characterized mind as ‘the steam above the factory’.

Epiphenomenalism is a view in philosophy of mind according to which some or all mental states are mere epiphenomena (side-effects or by-products) of physical states of the world. Thus, epiphenomenalism denies that the mind has any causal influence on the body or any other part of the physical world: while mental states are caused by physical states, mental states do not have any causal influence on physical states. Some versions of epiphenomenalism claim that all mental states are causally inert, while some versions claim that only some mental states are causally inert. The latter version often claims that only particular types of mental states that are especially difficult to account for in the sciences are epiphenomenal, such as qualitative mental states (e.g., the sensation of pain).

Background

One of the earliest views resembling epiphenomenalism was discussed by Thomas Huxley. Huxley (1874) likened mental phenomena to the whistle on a steam locomotive. However, epiphenomenalism flourished primarily as it found a niche among methodological or scientific behaviorism. Skinner began the attempt to uncover laws describing the relationship between stimuli and responses, without reference to inner mental phenomena. Instead of adopting a form of eliminativism or mental fictionalism, positions that deny that inner mental phenomena exists, a behaviorist was able to adopt epiphenomenalism in order to allow for the existence of mind. Participants in that revolution, such as Jerry Fodor, reject epiphenomenalism and insist upon the causal efficacy of the mind.

However, since the cognitive revolution, there have been several who have argued for a version of epiphenomenalism. These more recent versions, however, maintain that only the subjective, qualitative aspects of mental states are epiphenomenal. Unlike the robot, Pierre is conscious of eating the cupcake while the behavior is under way. This subjective experience is often called a quale (plural qualia), and it describes the private "raw feel" or the subjective "what-it-is-like" that is the inner accompaniment of many mental states. Thus, while Pierre and the robot are both be doing the same thing, only Pierre has the inner conscious experience.

Frank Jackson (1982), for example, once espoused the following view:

According to epiphenomenalism, mental states like Pierre's pleasurable experience—or, at any rate, their distinctive qualia—are just epiphenomena; Pierre, according to epiphenomenalism, might as well be a robot or a zombie, because conscious mental states do not affect his behavior. The conscious experiences that accompany brain processes are causally impotent.

Some critical responses

The philosophical behaviorists (as opposed to scientific behaviourists) reject epiphenomenalism on the grounds that it is, in Gilbert Ryle's phrase, a "category mistake."

Functionalists chart a different course, accepting that there is a system of mental events mediating stimulus and response, but asserting that this system is "topic neutral" and capable of being realized in various ways. The topic neutrality of the mind implies the denial of epiphenomenalism, which, as a kind of property dualism, fixes consciousness as a non-neutral, non-physical topic.

Eliminative materialists, on the other hand, assert that the concept of mind aims to fix reference to a non-physical topic; Eliminative materialism holds, however, that this dualistic aim of "folk psychology" is a fatal error built into mental concepts. Mackie called an error theory, stripping false beliefs away from the problematic concepts but not eliminating them, leaving intact a legitimate core of meaning.)

Arguments for

A large body of neurophysiological data seems to support epiphenomenalism. More recently Benjamin Libet et al (1979) have shown that it can take 0.5 seconds before a stimulus becomes part of conscious experience even though subjects can respond to the stimulus in reaction time tests within 200 milliseconds. Recent research on the Event Related Potential also shows that conscious experience does not occur until the late phase of the potential (P3 or later) that occurs 300 milliseconds or more after the event. This also suggests a delay for processing data before conscious experience occurs. Norretranders has called the delay "The User Illusion" implying that we only have the illusion of conscious control, most actions being controlled automatically by non-conscious parts of the brain with the conscious mind relegated to the role of spectator.

The scientific data seem to support the idea that conscious experience is created by non-conscious processes in the brain (i.e., there is subliminal processing that becomes conscious experience). These results have been interpreted to suggest that people are capable of action before conscious experience of the decision to act occurs. Some argue that this supports epiphenomenalism, since it shows that the feeling of making a decision to act is actually an epiphenomenon;

Arguments against

Many argue that data such as the Bereitschaftspotential undermine, rather than support, epiphenomenalism. Such experiments purport to measure the point in time when conscious experience occurs, which presumes that conscious experience has a measurable effect. Such a premise contradicts epiphenomenalism, which claims that conscious experience has no effects and therefore cannot be measured. Hence, so the argument goes, any experiment that detects whether or when conscious experience occurs argues strongly against, not for, epiphenomenalism.

A second common criticism of epiphenomenalism is that it feels like the mind has influence. William James urged something similar to this criticism against epiphenomenalism, which he called "Automatism":

However inadequate our ideas of causal efficacy may be, we are less wide of the mark when we say that our ideas and feelings have it, than the Automatists are when they say they haven't it.

Another criticism of epiphenomenalism is that the presence of the theory of epiphenomenalism seems to contradict the very idea. Most would agree that thinking is a mental process, but, if epiphenomenalism is true, how could someone ever express the idea of epiphenomenalism? If epiphenomenalism is true and thinking is a mental process, then its truth is ineffable.

Finally, many argue that the history of epiphenomenalism is revealing. It was concocted as a potential solution to a problem facing dualism: By what mechanism does the mental realm affect the physical? Epiphenomenalism provides an out: The mental realm simply doesn't affect the physical, so the issue is moot. Because it arose out of an attempt to save another conjecture rather than by its own merits, epiphenomenalism can be seen as suspiciously motivated. (1996) The Conscious Mind: In Search of a Fundamental Theory, Oxford: Oxford University Press. Pearl, "Subjective Referral of the Timing for a Conscious Sensory Experience", Brain, 194, pp. (1985) "Unconscious Cerebral Initiative and the Role of Conscious Will in Voluntary Action", Behavioral and Brain Sciences, 8, pp. (2003) "Epiphenomenalism", The Stanford Encyclopedia of Philosophy, Edward Zalta (ed.).