In The Antichrist, Nietzsche condemns Christianity for having no trace of any concept of natural causes and for positing a number of imaginary causes. Among these imaginary causes he lists the soul. (1) Although not systematically explicated, The Antichrist does offer an alternative to theological views of the soul in the form of a naturalized philosophy of mind. This naturalized point of view can be read as a modification of the Aristotelian theory of the soul found in the De Anima.
In The Antichrist, Nietzsche faults Descartes for reserving the appellation machina for animals, claiming that Descartes did not go far enough in analyzing man mechanistically. (2) Because of this reserve, Descartes was forced to invent an illusory mental substance as the only real, essential, human core. This simple mental substance - the I that thinks and exists independently of the body - is seen by Nietzsche as essentially the same illusory entity as the Christian soul. It has since been suggested, in fact, that Descartes offered a perfect compromise between the Church and the new science of physics with his mind/body dualism. (3) In any case, the derivation of man from any non-physical substance is a mistake according to Nietzsche because it "...falsifies, devalues, and negates reality." (4) Plato was one of the first philosophers to invert the natural order with his divided line, placing Ideas in a realm of higher reality than physical objects. (5) For Nietzsche, the divided line is upside down, and any attempt to demote physiological realities to a position inferior to non-physical substances is a mistake. The impulse to invert the natural order of things comes, so Nietzsche writes, from those who suffer most from their position in that order; namely the physiologically impaired. Consistent with his proclamation of the death of God, Nietzsche seeks to describe human beings as organisms governed not by some set of moral commandments, categorical imperatives, or higher beings, but by the necessities and contingencies of their natural environments. Human beings are organic machines, not spiritual prisoners trapped in cages of flesh and bone. He has placed man back amongst the animals (6), and in so doing intends to explain and describe man in the same terms as all animals. There is some debate as to how far Nietzsche intended this strategy to extend. Some authors feel that Nietzsche's is an all encompassing theory, meant to explain all worldly processes, while others feel that it is more restricted in scope, being intended to apply only to organisms or even only to human organisms. (7) But in The Antichrist, it is clear that Nietzsche makes a distinction between man and other organisms only insofar as man is a subset of the category "organism." After all, "...every living being stands beside man on the same level of perfection." (8) Moreover, if read through an Aristotelian lens, Nietzsche's theory emerges as an exhaustive description of all earthly processes.
In the De Anima, Aristotle posits three kinds of substance: matter, form and composite. Everything that exists falls on a continuum between matter and form. At one extreme end of the continuum lies pure matter; a material substance possessing pure potentiality and devoid of any form. Pure matter might be thought of as a kind of primordial "stuff" comprising the basic building blocks of all material things. Pure matter can potentially be anything, but must await the imposition of some kind of actual form in order to realize that potential. Pure form lies at the other extreme end of the continuum. It is a formal substance possessing pure actuality and devoid of any matter. Pure form might be thought of as God, the unmoved mover, or simply that which actualizes the potential in all things. Between these two extremes lies composite substance. Composite substance is material substance through which formal substance acts. Everything in our immediate environment is a composite substance, including humans and other organisms. (9) Nietzsche, in effect, curves Aristotle's matter/form continuum back upon itself in order to forge an eternally recursive loop. This modification eliminates the possibility of any pure matter or form. Everything that exists, in this schema, has to be a composite substance, and nothing exists that isnt composite. Caught in a Heraclitean struggle of opposites, the world emerges in an eternal process of actualizing potentialities. The question of God's existence as a pure, formal substance, or the question of the existence of any kind of fundamental, material substance is eliminated from this picture. Man, as a composite substance, is derived not from any supernatural force, but from the very same natural forces that shape every other existent thing in the world. He exists not as part of a "higher order," but as part of the "natural order."
Both Aristotle and Nietzsche are driven by a similar vision. Organisms are not to be separated from their environments, but are to be explained in the very same terms as their environments. Just as a rock is a composite entity arising out of the interaction of matter and form, so organisms are composite entities. But there is an obvious difference between a rock and an organism; namely that an organism has life while a rock does not. Aristotle explains this difference by attributing "souls" to living organisms. The Aristotelian soul describes the form of an organism by way of its function as the efficient (moving) and final (purposeful) cause of the organism. In short, the body is the material cause of an organism while the soul is the formal, final and efficient cause. Each type of organism possesses a soul which is appropriate to its function in the world. Plants possess the simplest type of soul, comprised of only a nutritive faculty, while animals have additional perceptive and locomotive faculties. The human organism is unique in that it possesses an intellective capability which allows for conscious thought. (10) Nietzsche advocates the recognition of certain natural causes, but rejects the concept of the soul in his explanation of life. Central to his causal interpretation is the "Will to Power." Though not a substance, Nietzsche's Will to Power is similar to Aristotle's conception of a soul insofar as it is described by the process that involves the organism in purposeful activity. For Nietzsche, every living organism possesses a certain quantum of energy, or power, which naturally tends towards expansion. Through the will, an organism channels and directs this power into work or activity. Imagine a bottle of pressurized air. The bottle can be hooked up to a variety of hoses, directing the expelled air into the service of filling balloons, turning windmills, or compressing springs. In this illustration, the bottle stands in for the body or matter comprising the organism. The pressurized air corresponds to power, the hoses to will, and the work performed to the purpose or goal of the organism. Translated into the language of the four causes, Nietzsche's explanation of life is remarkably similar to Aristotle's. The material cause of the organism is its physical body. The formal cause, which cannot be separated from the matter through which it acts, is the will. The efficient cause is the power which energizes the organism. The final cause is the purpose or end result that the power is channeled into by the will. Both Aristotle's theory of the soul and Nietzsche's theory of Will to Power can be characterized as describing the efficient, formal and final causes of living organisms. Nietzsche, however, must reject the existence of an entity called a "soul" because he does away with the possibility of formal substance when he turns Aristotle's matter/form continuum back upon itself. As pure form, the soul cannot possibly exist. It is a fiction, for Nietzsche, to speak of actuality without the potentiality of matter. The soul, if conceptualized as an actual, substantial entity, is simply an imaginary cause.
Aristotle thought that the human soul originated in the heart. The brain was simply an elaborate cooling system for the body. (11) Nietzsche did not share this belief, if only because he didnt believe in a thing called a soul. The structures of the brain, however, must have struck him as belying a function suited to far more than cooling the body. The evolution of the human organism is most profoundly characterized by the expansion of the brain; most notably the development of the cerebral cortex which is now believed to be the origin of all conscious thought and movement. The development of the cortex made communication and group living possible by way of giving humans self awareness. This self awareness gave man an advantage in the animal world, allowing him to find safety in numbers through conscious cooperation. (12) But the development of consciousness also facilitated the construction of superstitious speculations about the world. Conscious beings are in the position of recognizing their own composite natures and, by the exertion of will, actualizing their latent potentialities. When man gained consciousness, it became his privilege, amongst all other animals, to redefine his own final cause. This redefinition, according to Nietzsche, can be the most ennobling of activities - if it heightens man's feeling of power - or it can be the most decadent - if it denies his feeling of power. (13) The creation of imaginary causes, like the "soul" or "God," denies this power that man has developed over himself.
If the natural causes that Nietzsche refers to in The Antichrist are taken to be something along the lines of Aristotle's four causes, a comprehensive and coherent description of the world emerges. Nietzsche's theory can be interpreted as a non-substantialist modification of Aristotle's theory of the soul. Taken in this way it becomes possible to reconcile what seems to be a tendency towards causal determinism with Nietzsche's doctrine of self overcoming. In the mechanistic world view of Nietzsche, where natural causes are everywhere at work, it is only conscious organisms that have the power to deny or affirm their place in the world as organic machines.
(1) Friedrich Nietzsche, The Antichrist, in The Portable Nietzsche, trans. and ed. Walter Kaufman (New York: Penguin Books, 1984), pg. 581.
(2) Ibid, pp. 580 - 581.
(3) See for example, William Barrett, Death of the Soul, (New York: Anchor Books, 1986)
(4) Nietzsche, The Antichrist, pg. 580.
(5) See Plato, The Republic, trans. G.M.A. Grube (Indianapolis: Hackett, 1974), book VI.
(6) Nietzsche, The Antichrist, pg. 580.
(7) See Stephen P. Schwartz, The Status of Nietzsches Theory of The Will To Power in the Light of Contemporary Philosophy of Science, International Studies in Philosophy, Vol. XXV/2 (1993), pg. 85.
(8) Nietzsche, The Antichrist, pg. 580.
(9) Aristotle, De Anima, trans. Hugh Lawson-Tancred, (New York: Penguin Books, 1988), Chpt. 1, Book II.
(10) Ibid, Chpts. 2 - 12, Book II.
(11) The Brain, ed. Roy Pinchot, (New York: Torstar Books, 1984), pg. 9.
(12) Nietzsche, The Antichrist, pg. 593.
(13) Ibid., pg. 570.