Mini lecture 2: Epiphenomenalism

Epiphenomenalism is a position in the philosophy of mind according to which mental states or events are caused by physical states or events in the brain but do not themselves cause anything.

It seems as if our mental life affects our body, and, via our body, the physical world surrounding us: it seems that sharp pains make us wince, it seems that fear makes our heart beat faster, it seems that remembering an embarrassing situation makes us blush and it seems that the perception of an old friend makes us smile.

In reality, however, these sequences are the result of causal processes at an underlying physical level: what makes us wince is not the pain, but the neurophysiological process which causes the pain; what makes our heart beat faster is not fear, but the state of our nervous system which causes the fear etc.

According to a famous analogy of Thomas Henry Huxley, the relationship between mind and brain is like the relationship between the steam-whistle which accompanies the work of a locomotive engine and the engine itself: just as the steam-whistle is caused by the engine’s operations but has no causal influence upon it, so too the mental is caused by the workings of neuro-physiological mechanisms but has no causal influence upon their operation.

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The doctrine that consciousness, or mind, is an added or secondary phenomenon (epiphenomenon); the doctrine that consciousness is the incidental result of the phenomena of neural structure and of neural activity according to the laws of mechanics. 

 According to this view, freedom and responsibility are illusions or a routine, having no more real relation to conduct than has the sound of the bell to its tolling or the whistle of the engine to its movements. 

The aim of science is held to be the objective study of a material universe, into which our minds must not be thrust as part of the problem, which is complete and intelligible only when considered objectively and as separated from our minds by a chasm that is intellectually impassable. 

Sensible knowledge is held to consist of phenomena or appearances which are produced in our minds by a natural world that in itself is, and always must be, utterly unknown and unknowable; and as the human brain is part of the phenomenal world of appearances in our minds, critical epiphenomenalism resolves itself into the assertion that our minds are the by-products of appearances in our minds, produced by we know not what.