The concept of happiness, or eudaimonia in Aristotle's terms, has been a central concern for philosophers since antiquity. While both Immanuel Kant and Aristotle identified happiness as a significant human good, their understanding of its nature, its attainment, and its place within a moral life diverged considerably. Aristotle posited happiness as the ultimate human end, achievable through virtuous activity in accordance with reason. Kant, conversely, viewed happiness as a conditional good, secondary to moral duty and the good will, and ultimately unattainable through purely human effort in this life. Examining their differing frameworks reveals fundamental contrasts in their ethical systems, particularly concerning the relationship between morality and well-being.
For Aristotle, as articulated in the Nicomachean Ethics, happiness is not merely a fleeting feeling of pleasure but a state of flourishing, an activity of the soul in accordance with virtue. He argued that every art and every inquiry, and likewise every action and pursuit, aims at some good, and the highest good is what we desire for its own sake, which he identified as happiness. This happiness is achieved through the cultivation of moral and intellectual virtues. Moral virtues, such as courage, temperance, and justice, are developed through habituation, finding the mean between extremes. Intellectual virtues, like wisdom and understanding, are acquired through teaching and experience. Reason plays a crucial role; it is the distinctive function of humans, and living well means exercising this rational capacity excellently. Aristotle’s ethics is teleological, meaning it is concerned with ends or purposes. The telos, or final end, for humans is eudaimonia, a life lived well and flourishing. This flourishing is an objective state, measurable by one's actions and character over a complete life, not by subjective feelings.
Kant, on the other hand, presents a deontological ethical system, where morality is based on duty and adherence to universalizable moral laws, rather than on the consequences or ends of actions. In his Groundwork of the Metaphysics of Morals, Kant argues that the only thing that can be called good without qualification is a good will. A good will is good not because of what it achieves, but because of its willing – it acts from duty, out of respect for the moral law. Happiness, Kant contends, is a "perpetual gain" that can be achieved through empirical means, but it is not the ultimate good. He notes that the inclination to seek happiness is a natural human drive, but it is contingent and subjective. Furthermore, the pursuit of happiness can sometimes conflict with moral duty. For instance, a shopkeeper might be honest not out of duty but to maintain a good reputation and thus increase profits. For Kant, this action, though conforming to duty, lacks true moral worth because it is not done from duty. He also argues that happiness is not a reliable guide to morality because it is often based on inclination and can lead to actions that are not universally good.
The fundamental divergence lies in their conception of the highest good. For Aristotle, the highest good is happiness, understood as virtuous activity. For Kant, the highest good is the union of virtue and happiness, where virtue is the supreme condition of the good will, and happiness is a secondary, though desirable, good that is often seen as a reward for virtue, especially in his later work where he introduces the "highest good" as a postulate of practical reason in the Critique of Practical Reason. However, Kant is cautious, suggesting that in this life, we cannot guarantee that virtue leads to happiness. The pursuit of happiness for its own sake, divorced from duty, is morally suspect. True moral worth comes from acting from duty, even if it means sacrificing one's own happiness.
This contrast has significant implications. Aristotle’s system offers a comprehensive account of human flourishing, integrating virtue, reason, and well-being into a coherent vision of the good life. His emphasis on character development and practical wisdom provides a framework for living a fulfilling existence. Kant’s ethics, however, prioritizes moral integrity and the autonomy of the will. It offers a rigorous standard for moral action, emphasizing the importance of universalizable principles and the inherent dignity of rational beings. While Aristotle sees happiness as the end of a virtuous life, Kant sees the moral law as the primary determinant of worth, with happiness being a conditional and often uncertain accompaniment.