I have recently been attempting entrance into the deeper caves of subtleties in Nietzsche's thought on the mind and action. Nietzsche, so far in my understanding from reading both him and secondary literature, seems to assert that the mind is epiphenomenal (from a phenomenological account of action), and that our consciousness does not actually cause actions. A couple weeks ago, I discussed this topic after reading a related article.
Basically, Nietzsche asserts that our body is composed of many drives, and that these drives play out their interactions, and the (ongoing) result of this struggle is a deep cause. This deep cause then causes both our motor action and our sense of desire for wanting to act out that motor action. In other words, our mental desires (i.e. motives or intentions) do not cause actions, but rather, a deep cause causes both our mental desire to act and a corresponding action.
From this epiphenomenal picture of mind and action, I began to ask myself, "what is the purpose of this consciousness that does not cause actions?"
(Against the notion of free will, there is an experiment that shows that when you move your hand, the nervous system signal to move your hand becomes active significantly, a few hundred milliseconds, before the person's conscious brain becomes aware of the desire to act ("Bereitschaftspotential"). There is also some contemporary, psychology literature on related epiphenomenal themes, a book I am interested in reading).
To answer this question, as to the purpose of consciousness, all I can conceive of is that consciousness (our subjective perspective) is the visual throne of the body (the primary location of sensation collection). (However, there can be other secondary locations of sensation collection, for example, reflexes that synapse sensory neurons and immediately fire back motor neurons from the spine or even unconscious perceptions, as with blindsight.)
Therefore, whichever drive or set of drives wins out in the "unconscious" struggle (among drives) is then able to temporarily appropriate the visual throne for their advantage. What is the advantage of this appropriation?—that with consciousness, a drive can monitor whether or not its resultant "deep cause" was carried out, and through consciousness, the drive can receive feedback (the strength of the drive can be reduced after the "mental desire" is satisfied).
Having a consciousness allows the body to translate the drives into the organized symbols, shapes, words, flavors (qualia) of our conscious experience in order to effectively satisfy the drives and give them feedback. What is the role of language?—could it be a way for consciousness to simplify the manifold multiplicity of sensations and make it easier for a drive to discern among (conscious) sensory possibilities.
I'm trying to decide if we can say that consciousness does not cause any actions at all or just that consciousness causes very few actions (but that it's nonsensical to identify with these few actions caused by consciousness any more than to identify with actions caused by unconscious processes). Perhaps my thoughts are getting mixed up in this unrefined use of language.
Wikipedia says, epiphenomenalism denies that the mind (as in its states, not its processing) has any 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 influence on physical states ("Epiphenomenalism"). I don't mind reducing the role of consciousness; however, it doesn't seem to make sense to delete its role altogether (then my experience would just be an inert event). However, I agree with the physicalism that epiphenomenalism implies, that (from a third-person perspective) our actions are the cause of our physiological type-facts and our (social and material) environment, not of a transcendent mind that appears to exist from the first person.
Also, it would make sense if mental states reduced to physical states; however, it seems to me that I am creating problems here by conflating various uses of the term consciousness. Isn't epiphenomenalism a term meant to describe our first-person (phenomenological) experience of what is (from a third-person perspective) an embodied series of physical processes. Therefore, I should be saying "the first-person experience of consciousness is epiphenomenal," while "the material processes that generate such things that we call "consciousness," "actions," "desires," and "unconscious events" are all physical and that it would be nonsensical to call consciousness transcendent from a third-person perspective because these processes occur in a material environment (material body) and because such a thing as a "mind" is nonsensical from a third-person perspective."
In a physical sense, the parts of the brain that we call consciousness (a map constantly shifting per their activation) are those parts which monitor whether or not a desire is satisfied and the desire is stopped (satisfied) when a sufficient stimulus is received; additionally, when a desire is stopped, a different desire is then being monitored. Hence, consciousness, even as a physical entity, remains on the receiving end of sensation; however, it still has a significant role (perhaps, it is that, as humans, we are accustomed to valuing things highly based on their ability to act and this inability to act seems to render consciousness valueless). Nevertheless, consciousness acts indirectly by organizing sensory information (both the affects of drives and the sensations of the environment) to compel, via focusing, several activities among possible activities. However, the focusing, the compulsion, is the result of events outside of consciousness; nevertheless, the fact that consciousness has an ongoing role means that it is essential part of our activity.