Nietzsche also thought that life wasn’t only about self-preservation and mere survival (a position he took Darwinists to be arguing for) but that life was intrinsically aiming toward multiplication and extension, that it was governed by fundamental “a will to power” (here we have another very problematic concept of Nietzsche which no one really seems to understand).
“What then is the purpose of consciousness generally, when it is in the main superfluous?”
“where necessity and need have long compelled men to communicate with their fellows and understand one another rapidly and subtly, a surplus of the power and art of communication is at last acquired, as if it were a fortune which had gradually accumulated, and now waited for an heir to squander it prodigally.“
“consciousness generally has only been developed under the pressure of the necessity for communication “
Furthermore, consciousness is mainly necessary in social settings:
“consciousness is properly only a connecting net between man an man, - it is only as such that it has had to develop, the recluse and wild-beast species of men would not have needed it.”
Humans are seen as the “most endangered animal” in need of help and protection. This is also eched in famous German philosophical anthropologist Arnold Gehlen's concept of humans as "Mängelwesen" (deficient creatures), i.e. organisms with deficient instincitve capacities which leave them ill-prepared to respond to challenges from their environment. I think formulated in the way Gehlen does it the notion is crap, but it is certainly true that human are adapted for the "cognitive niche" and do not rely on predatory skills such as lions, etc, and are much more fragile and helpless to such attacks.
In order to express and coordinate this need, they needed to make themselves understood, and they needed to have a capacity for conscious introspection in order to know and communicate what they needed and wanted. In modern terminology, this would probably be called metacognition. To be more precise, given modern terminology, Nietzsche would probably hold that animals may display metacognitive regulation, e.g. higher-order sub-conscious uncertainty monitoring, as it has been shown in macaques and dolphins (Smith et al. 2003). This sort of higher-order subconscious thought would probably be what Nietzsche would refer to as unconscious thinking. However, together with other modern philosophers, he would probably hold that only humans display metacognitive knowledge (a distinction introduced by Flavell 1979, see also Hurford 2007: 23ff.).
“The sign-inventing man is at the same time the man who is always more acutely self-conscious, it is only as a social animal that man as learned to become conscious of himself“”
“consciousness does not properly belong to the individual existence of man, but rather to the social and gregarious nature in him; […] as follows therefrom, it is only in relation to communcal and gregarious utility that it is finely developed; and that consequently each of us, in spite of the best intention of understanding himself as individually as possible, and of “knowing himself”, will always just call into consciousness the non-individual in him, namely, his “averageness.”"
But Nietzsche goes even further: given that conscious is essentially something that develops in group interactions, if we translate our actions into conscious decisions, they all have to adhere to the same conscious group format, and thus lose their personality, uniqueness, and individuality:
“The nature of animal consciousness involves the notion that the world of which we can become conscious is only a superficial and symbolic world, a generalised and vulgarized world; […] everything which becomes conscious becomes just thereby shallow, meagre, relatively stupid, a generalisation, a symbol, a characteristic of the herd; […] with becoming conscious of something there is always combined a great, radical perversion, falsification, superficialisation, and generalisation.”
Nietzsche’s closes with a sceptically remark that is very similar to the viewpoint of modern, evolutionary epistemology, and which is also close to the following fear espressed by Charles Darwin:
"But then with me the horrid doubt always arises whether the convictions of man’s mind, which has been developed from the mind of the lower animals, are of any value or at all trustworthy.”
Nietzsche also shares this scepticism. If consciousness is merely a group function and not responsible for higher-order thought, then
“we have not any organ at all for knowing, or for “truth”: we “know” (or believe, or fancy) just as much as may be of use in the interest of the human herd, the species; and even what is here called “usefulness,” is ultimately only a belief, a fancy, and perhaps precisely the most fatal stupidity by which we shall one day be ruined”
Flavell, John. (1979). Metacognition and cognitive monitoring: A new area of cognitive-developmental inquiry. American Psychologist 34, 906–911.
Hurford, James M. (2007): The Origins of Meaning: Language in the Light of Evolution. Oxford: OUP.
Metzinger, Thomas (2000): The Subjectivity of Subjective Experience: A Representationalist Analysis of the First-Person Perspective. In: Thomas Metzinger (ed.): Neural Correlates of Consciousness – Empirical and Conceptual Questions. Cambridge, AM: MIT PressPinker, Steven 1994. The Language Instinct: The New Science of Language and Mind. London: Lane Penguin Press.
Smith, J. D., W. E. Shields, and D. A. Washburn (2003a). The comparative psychology of uncertainty monitoring and metacognition. Behavioral and Brain Sciences 26, 317–339.