Reason vs. Passion: Comparing Aristotle and Plato

Introduction: Beyond the Head-or-Heart Dichotomy

It is well known among students and scholars of philosophy that both Plato and Aristotle hold reason in high regard. But what is their view on passion? It may be surprising to learn that neither philosopher holds a negative view of passion in and of itself. What both thinkers do point out, however, is that passion should be subservient to reason. Passion governed by reason is not a bad thing for either philosopher, and what is more important is that some passions or emotions should be promoted over others (Urmson; Taylor).

The problem that most modern readers have when it comes to understanding what passion means is that they define the term in all-or-nothing terms, applying a kind of either/or approach to the question of whether one should live by the head or the heart. Both Plato and Aristotle supported some degree of combination — that is, that head and heart should be in alignment for happiness to be achieved, and that both should be oriented towards the good. For moderns influenced by the philosophy of the Romantic Era, passion is associated with unrestrained feeling, or with the heart serving as the sole guide and arbiter of action. Understanding the ways in which Aristotle and Plato conceived of passion and emotion, and how they associated it with reason, is therefore essential to understanding the nature of the relationship between reason and passion.

The Conflict: What Should Rule, the Head or the Heart?

The conflict over whether the head or the heart should be the governing voice of action has been of particular concern in the modern era. It was the Romantic Age that gave such strong support to the heart, partly in response to the Enlightenment, which had advocated solely for Reason. The French Revolution, after all, enshrined Reason and effectively deified it, operating on the assumption that man needed nothing more than logic. It is not surprising, then, that humanity, sympathy, empathy, and compassion were utterly absent during the Reign of Terror that followed. The Revolution demonstrated that when man gives himself over wholly to Reason while neglecting the impulses of the heart, absolute horror can result. The bloodletting that transpired during the Reign of Terror in Paris substantially bears this out.

At the same time, the Romantic Age went in the opposite direction, essentially deifying feeling and emotion as that which should guide life. Feelings, as long as they were passionately felt, were all that mattered — and this in turn led to its own set of problems for those who followed this line of thinking. Percy Bysshe Shelley, for example, left a string of deaths in his wake as he pursued the grand feelings and emotions he celebrated in his poetry. His wife, Mary Shelley, turned Percy's pursuit of feeling into the basis of her gothic horror novel Frankenstein, which told of a man consumed by passion, which in turn begets a monster that destroys the life and work of its creator.

In both ages — the Enlightenment, in which Reason was upheld above all else, and the Romantic Age, in which Passion was upheld as the supreme guiding force — unspeakable horrors resulted, indicating that the all-or-nothing approach to whether the head or the heart should rule was too extreme. Neither Plato nor Aristotle advocated such an extreme position. On the contrary, each in his own way advocated for a balance, or at least an alignment between the two, in which both were oriented towards the higher ideal of goodness. Though each philosopher differed in his approach to this balance — in terms of whether reason should be viewed as an end in itself or as a tool to be applied to daily life — the essence of their perspectives was that reason should govern passion, or that passion, at least, should be oriented towards reason.

Plato: The Soul, Spirit, and the Role of Reason

To understand Plato's approach to this question, it is necessary to understand his view of human nature. Plato believed that man had a soul and that the soul was what animated man in his entirety. The soul possessed qualities that were manifested in a person's approach to life. It had knowledge written upon it, had impulses that could be driven by base desires, and had a spirit that could be described as good or bad depending on how close in proximity it was to the Good.

John Cooper points out Plato's depiction of the soul by explaining its three basic characteristics: "reason, spirit and appetite" (3). According to Plato, these three distinct parts may be independent of one another, but they are actually meant to act harmoniously — "that is to say, there are desires of reason as well as bodily appetites and impulses of a spirited nature" (Cooper 5). By identifying the aspects of the soul in this way, Plato is not drawing them into competition with one another but rather showing how they are all sides of human life — aspects of the human will and of the motivating force of life. Reason and passion (whether spiritual or physical) are not to be thought of as conflicting or contradictory, because the point for Plato is that they can be mutually reinforcing. In other words, they can and should work together, and when they do, human life achieves a harmonious balance — the type of balance that people are meant to enjoy.

With that said, the opposite can also occur if one lets feeling dominate or run amok. Plato devotes considerable attention to describing the meaning of these two aspects of the soul and juxtaposing them with reason in order to show how they are in fact distinct. Taylor states that "the difference between the treatments of appetite and spirit (thumos) is instructive" (12). Spirit is not defined simply, nor can it be viewed as wholly good or wholly bad. It is rather like what Aristotle describes as the overall character of a person. For Plato, spirit resists so neat a description and is instead loosely defined by way of analogy.

For instance, Plato gives the example of Odysseus as the rational man who on occasion allows his spirited qualities to take possession of him. Using this example, Plato shows that "spirit is a complex form of motivation whose primitive form is anger, and whose conceptual core is a sense of self-worth which manifests itself in such emotions as pride, shame, and indignation" (Taylor 13). For spirit to be good, it must be monitored and measured, for, "like bodily appetites, these emotions too can be recalcitrant to reason, as in the case of Odysseus, whose anger at the outrageous conduct of Penelope's maidservants with the suitors threatens to carry him away and has to be checked by his better judgment (441b–c)" (Taylor 13). Spirit must be able to work with one's "better judgment" — that is, one's reason — in order to ensure that the Good is always made possible.

The simple fact that spirit is something that can be checked by reason reveals precisely what Plato believed: passion is part of the human experience and is not bad in and of itself, as it is partly what serves as the motivating force of life — but it must be governed by reason. The head must govern the heart and master its emotions, lest the emotions lead the rest of the person into trouble, as would surely have been the case had Odysseus allowed his offended pride to overcome him in the heat of the moment.

As it was, Odysseus gained mastery of his emotions and then set about devising a plot to ensnare the suitors and win back his home, as Plato shows. Passion thus served to motivate him, but reason was used to guide that passion and make it as productive as possible. Without the spirit and appetite qualities of the soul, Odysseus would have been like a disembodied head — all reason and no heart. But mankind has both head and heart, which is, of course, Plato's point. The heart and the head must work in unison, and neither should be trusted without the other.

Why are these aspects of the soul central to Plato's conception of how reason and feeling should go together? The answer is that the soul is the central mystery of humankind. It is the one feature that distinctly differentiates mankind from everything else in creation, and yet it is the least defined or understood aspect of humanity. Without the soul, there can be no meaningful discussion of reason, passion, or desire, for these qualities emanate from the soul, according to Plato.

Understanding passion and reason merely as aspects of biology, of the mind, or as random impulses is insufficient to grasp the most significant point of life, which is the soul's desire for union with the Good — the source of all that is good in the world. This point lies at the heart of many of Plato's Dialogues, and in Phaedo in particular Plato gives a great deal of attention to a discussion of the soul and how knowledge is obtained. Plato argues that ideas are written on the soul at its creation and that knowledge is simply an act of recollection — seeing what is already inherent in the soul. The soul is thus a great repository of all the information given to man by the Good, which exists for all eternity.

For example, Plato, using the character of Socrates, emphasizes the importance of the soul and its ultimate destination when he states, as Furlong notes, "for if the soul exists in a previous state, and if, when it comes into life and being, it can only come from death and the state of death, must it not also exist after dying, since it must again come into being (Phaedo, 77 c-d)" (65). Plato highlighted the immortality of the soul in order to show that man was not meant just for this finite earth but rather for something greater and beyond this world.

For Plato, the soul was of the same essence as that of God — not equal to God, but of some spiritual and intellectual quality similar in aspect to that divine essence. The soul, being from God, naturally desired to be like God or with God, and as it had the instructions from God written upon it, the soul was inclined to know these instructions, recollect itself in knowledge, and pursue the good that God had designed it to be part of. The soul's defining features — reason, spirit, and appetite — were thus the impetus behind the soul's craving for knowledge, action, and orientation toward the good or the transcendental ideals. Plato points to the Good as the transcendental idea, but it is Aristotle who gives the most sustained attention to the concepts of "being" and "the one" in his Metaphysics.

Conclusion: Head and Heart in Harmony

The aim of Plato was to show that the use of reason in pursuit of the highest ideal was mankind's greatest challenge and noblest task. Plato loved to use his intellect to consider all things, to know truth and to know himself. Aristotle saw reason as having a more pragmatic or practical application: he wanted to show that people could use reason to know good from bad, right from wrong, and then form their characters so that their likes and dislikes conformed to what their head knew was good and bad. Aristotle saw head and heart working in unison as a necessity for happiness. Plato saw pouring one's heart into the efforts of the head to know truth as a sufficient use of one's time in and of itself.

Both ultimately arrived at the same point — namely, that head and heart must work in harmony. Each said as much in different ways, using different terms and methods of illustrating their point — but in the end, the lesson they teach is that reason must govern passion so that mankind can truly be happy.

Aristotle. Nicomachean Ethics. Chicago: University of Chicago, 2011.

Cooper, John. "Plato's Theory of Human Motivation." History of Philosophy Quarterly, vol. 1, no. 1 (1984), pp. 3–21.

Furlong, E. J. "Two Arguments in Plato's 'Phaedo'." Hermathena, vol. 30, no. 55 (1940), pp. 62–72.

Hardie, W. F. R. Aristotle's Ethical Theory, 2nd ed. Oxford: Clarendon Press, 1980.

Taylor, C. C. W. Pleasure, Mind, and Soul: Selected Papers in Ancient Philosophy. Oxford University Press, 2008.

Urmson, J. O. "Aristotle's Doctrine of the Mean." American Philosophical Quarterly, vol. 10, no. 3 (1973), pp. 223–230.