Aristotle believed that humans have a purpose which is the fulfillment of human nature, the aim of the good life. While many goals in life merely lead to further additional goals, such as the goal of making money leading to the goal of pleasure or security, Aristotle that there must be a final goal, an end in itself. What is this final goal, which should be universal and common to all of humanity? Sappho wrote that each person has something, often different things, that make them happy. For Aristotle, this subjective relativism is not good enough. If we are to understand human nature and the form of the good life, we must find something which is pursued for its own sake and universally valued. This is similar to Socrates in Plato’s Meno, who argues that the good must be the same for all in common. It is reason, the work of philosophy and science, which is the realization of the human, the fulfillment of human nature.
Like his teacher Plato, Aristotle argues that each of the three parts of the soul can be virtuous in their own way. The lowest center of desire, situated in the stomach, is virtuous when it promotes bodily health, what Aristotle calls nutritional virtue. The second center of spirit, situated in the chest, is virtuous when it promotes discipline and justice, what Aristotle calls moral virtue. Finally, the highest center of reason, situated in the head, is virtuous when it promotes study, investigation and contemplation, what Aristotle calls intellectual virtue. Aristotle believes that intellectual virtue leads to moral virtue, and moral virtue leads to nutritional virtue. When we are wise, we are moral, and when we are wise and moral, we are healthy. When we are unhealthy it is because we are undisciplined, and when we are undisciplined it is because we are unwise. A healthy person may not be wise or disciplined, like a talented artist who is neither courageous nor wise, in which case they will likely not remain healthy or talented for long. Similarly, a spirited and disciplined person may be healthy but not be wise, like an athlete or warrior who does not consider the larger picture before acting, in which case they will likely not remain disciplined or healthy for long.
At first, human individuals are neither wise nor disciplined. They must be taught wisdom and discipline by others who are already rational and moral, and then through practice develop what they receive from others to become rational and moral themselves. In acquiring intellectual, moral and nutritional virtue we find that a balance between extremes is best, what Aristotle calls the Doctrine of the Mean. ‘Mean’ here is the middle, not ‘mean’ as rude or aggressive. In all things, we must chart a middle course between excess and deficiency, too much or too little, the two opposite extremes. Aristotle uses the example of gymnastic exercises, which make an individual strong when there is neither too little or too much. Similarly, we should not eat too much or too little if we want to be healthy, as well as not study too much or too little if we want to be wise. Wisdom tells us when we are being too brave or too cowardly, fearing too much or too little.
Aristotle argues that there are many virtues, each a mean between a vice of excess and a vice of deficiency. Courage is the mean between haste and cowardice. Temperance is the mean between being too sensitive and too insensitive. Nobility is the mean between vanity and lack of self worth. Sincerity is the mean between boastfulness and self-deprecation. Wittiness is the mean between being too silly or too somber. Modesty is the mean between being too bashful and too shameless. Just like Aristotle’s categories, some of these are interrelated, not categorically distinct, and Aristotle is only somewhat successful at distinguishing them from each other. Like Aristotle, Buddha and Confucius argued that virtue is a balancing act between extremes.
Like virtue, Aristotle believes that justice is itself a balancing act. Agreeing with Plato’s form of the soul found in the Republic, which holds that justice is the lower put in check by the higher, Aristotle emphasizes that this is achieved by moderation. Justice has two sides, distribution of rewards to those who do good, which Aristotle calls distributive justice, and punishment to those who do wrong, which Aristotle calls corrective justice. Distribution and correction, also known as “the carrot and the stick” in the British folk tradition, is used to direct society, planned rationally by the philosophers and implemented courageously by the police.
Conflicts of desire, like social conflicts in the city, result in imbalance, in excess and lack. Socrates argued in Plato’s Republicthat no one would knowingly do evil, as they would see that it is not in their best interest, so a conflict in desires can lead to ignorance and a lack of courage or wisdom. For Aristotle, it is possible for a person to knowingly do evil when they are conflicted, as they can see what the wisest or courageous choice would be but are too overwhelmed by an excess of desire or honor to do what they know to be right. In these cases, when our desire for pleasure outweighs our wisdom, we can knowingly do the wrong thing. Socrates, like the Neo-Confucian philosopher Wang Yangming, would say that if a person does not do what is right, then they may say they know what is courageous or wise but they in fact do not know, cannot be said to see what is good, and are merely telling others what they expect they want to hear.
Miguel Leon-Pontilla argues in his Aztec Thought and Culture that the Aztecs and Mayans had theoretical philosophy like the Greeks, and that a central ethical concept similar to Confucius in China and Aristotle in Greece is “You are my other self”. Aristotle argues that to be ethical is not only to love oneself in moderation, but to love others and the cosmos in moderation, sharing your life in common. Like the Nous of Plato’s Timaeus, which simply contemplates in itself, justice and virtue, like friendship between individuals and scientific comprehension of the cosmos, is sought not because it is pleasurable but because it is an end in itself, a purpose above which there is none higher. While pleasure does follow from science and friendship, these are pursued for their own sake even when they do not result in pleasure, even when we learn truth we find unpleasant or must deal with situations we find difficult. By relating to others through friendship and to the cosmos through investigation and contemplation we complete ourselves, fulfill our human nature and achieve our highest purpose.