Why Aristotle Couldn't Avoid Metaphysics in The Nicomachean Ethics (Part I)

Aristotle’s vast corpus covers nearly every topic in philosophy and much of what we would know count as social or human sciences (political theory, economics, rhetoric and communication, literary criticism, linguistics). The extent of his productivity inevitably raises questions of an architectonic sort: how does the whole edifice fit together? I’d like to address briefly one question of this sort: in particular, how do Aristotle ethical works (the Nicomachean and Eudemian Ethics, and the Politics) relate to his work on metaphysics and natural philosophy? For our purposes today, I will focus exclusively on The Nicomachean Ethics. In particular, I will examine the first seven chapters of Book I.
 
I take it that for Aristotle ‘ethics’ and ‘politics’ are essentially synonyms, differing only in connotation. Since human beings are by nature political animals, the study of the human good (i.e., ethics) must coincide with the study of the common good (politics). For this talk, I will simply refer to this science as ‘ethics’.
 
In chapter 1, Aristotle makes clear that ethics is the science which studies the greatest human good. This immediately raises the question of whether ethics is a theoretical or practical science. In chapter 1, Aristotle doesn’t yet commit himself, calling the study an ‘episteme or dynamis’, where ‘dynamis’ (a power or faculty) would seem to suggest a practical science.
 
Practical and theoretical sciences differ in their ultimate ends. A theoretical science aims ultimately for the truth about some subject matter. It contributes to human happiness by providing us such truths as objects of our understanding and contemplation. So, theoretical sciences do contribute to the human good, but their definition is that of the pursuit of certain truths for their own sake.
 
In contrast, a practical science is one whose ultimate end is the human good itself. Does this mean that a practical science is indifferent to the truth as such? Would a practical science embrace a fiction or a falsehood if accepting it would make the greatest possible contribution to the human good? I take it that Aristotle is confident that this question is merely hypothetical, relying on an impossible antecedent. The most effective practical science is one that reliably uncovers the truth about the human good. In chapter 1, Aristotle affirms that our knowledge (gnosis) of the good is of great practical importance, since through our knowledge of the good we “have a target” to aim at, like the archer. So, both practical sciences and theoretical sciences aim at the truth.
 
The difference consists in the ultimate purpose of the science. For a practical science, truth is pursued for the sake of the good, while in a theoretical science, truth is pursued for its own sake. Any significant truth is something whose contemplation is good for human beings, but this fact is incidental to the purpose of a theoretical science. For a practical science, in contrast, truths are pursued only to the extent that they contribute to the guidance of our actions toward our good.
 
Metaphysics and natural philosophy (the subjects of the Metaphysics and the Physics) are paradigmatically theoretical sciences. Consequently, the distinction between ethics and metaphysics is a deep one. Neither science can be subordinated to another. For one science to be subordinated to another, either both are theoretical or both are practical. For example, the science of harmonics is subordinate to arithmetic, since harmonics draws its first principle from arithmetic. In this case, both are theoretical sciences. In the practical sphere, the science of horsemanship is subordinate to military strategy, since the use of horses is governed by the more ultimate end of military victory.
 
We would expect to see metaphysics and ethics differing both in their starting points and in their ultimate destinations, and this expectation is largely borne out by comparing the Nicomachean Ethics with Aristotle’s Metaphysics. In particular, we can see in Book I consistent effort on Aristotle’s part not to rely on specifically metaphysical principles or conclusions. There are, however, two prominent exceptions, to be found in chapters 6 and 7 of the first book. In these chapters, we see Aristotle compelled, albeit reluctantly, to bring to bear his specifically metaphysical knowledge.
 
There is, undoubtedly, in chapter 2 some overlap between ethics and metaphysics. I have in mind Aristotle’s rejection of the possibility of an infinite regress of means for further means: “We do not choose everything for the sake of something else, for at that rate the process would go on to infinity, so that our desire would be empty and vain.” Clearly, this parallels Aristotle’s rejection of infinite regresses of efficient and final causation in both the Physics and the Metaphysics. However, he does not in chapter 2 reject the possibility of an infinite regress in final causation on metaphysical grounds, but rather on the grounds that our desire in that case would be “empty and vain,” a specifically ethical or axiological consideration.
 
In chapter 6, Aristotle turns a critical eye on Plato’s theory of the Forms. This is undoubtedly a metaphysical theory, but it is relevant here because of Plato’s conception of the Form of the Good, which plays a central role both in Plato’s metaphysics and in his ethical theory. In fact, if there were such a thing as the Form of the Good, the distinction between metaphysics and ethics would utterly collapse. Understanding the Form of the Good for its own sake would be the central and definitive task of both ethics and metaphysics.
 
Consequently, Aristotle is forced at this point to consider a metaphysical question: is there such a Form of the Good? Nonetheless, in this chapter Aristotle provides several specifically ethical objections to the theory of the Form of the Good, objections that we do not find in the Metaphysics. For one, Aristotle argues that if there were a Form of the Good, there would be only one practical science (i.e., the metaphysics of goodness), but in fact there are many such science, including agriculture, medicine, and military strategy.  All these practical sciences are subordinate to ethics, but the fact of their existence supports Aristotle’s metaphysical thesis that goodness is attributed analogously and not univocally of different kinds of things. Just as ‘being is said in many ways,’ so is ‘goodness said in many ways.’ The diversity of practical science points to a diversity of goods that is inconsistent with Plato’s theory.
 
Aristotle also gives a more direct argument for the diversity of goods, pointing to the many different things that we can reasonably seek for their own sake, including honor, wisdom, and pleasure. If goodness were one and simple, then each of these kinds of goodness would have a common definition or account. And yet clearly pleasure and wisdom are good in different ways. Their goodness cannot be reduced to a common denominator.
 
However, in addition to these specifically ethical arguments, Aristotle feels compelled to appeal to metaphysical objections to the Form of the Good, objections that do have parallels in the Metaphysics and other texts. I count three such arguments:
 
1.The good transcends the categories of things, as Aristotle enumerates them. There are good people and other substances, good quantities, good qualities, good places, good times, good relationships, and so on. One Form cannot be present in the same way in things belonging to such fundamentally different ontological categories.

2.The form of the good cannot be a paradigm of goodness, since this would require the good to be both (i) eternal and world-transcending, and (ii) just like all other good things, albeit to a greater degree. However, being eternal and other-worldly would not make the Form of the Good better than all other goods—it would just make it radically incommensurable with them.
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3.The ‘third man’ problem. If The Man Itself (the Form of Man) and particular men agree with each other precisely in being men, then we are left with no explanation of how the Form of Humanity can be human, unless we posit a further Form of Humanity shared by this first Form of Humanity and all particular men, resulting in an infinite regress.
 
Aristotle tries to cut short his discussion of these objections on the grounds that “perfect precision about them would be more appropriate to another branch of philosophy” (i.e., metaphysics). Nonetheless, a certain quantity of metaphysical knowledge is needed in our ethical investigations, if only to preserve ethics from contamination by bad metaphysics.