An obsessive writer, who worked with multiple drafts of his texts, Plato paid careful attention to the dramatic settings of the dialogues he composed.
At the beginning of Phaedrus, for example, Socrates and his companion, who lends the name to the title of the exchange, find themselves in the countryside. Phaedrus singles out a particularly auspicious place for the rest of the conversation — a soft patch of grass shaded by a tall plane tree, platanos (229a-b).
Does the idyllic natural setting, outside the circumscribed space of the city-state, stand for a counterweight to the despised excesses of civilization? Not quite.
A few pages into the dialogue, Socrates will confess: “You see, I am fond of learning. Now the country places and the trees won't teach me anything, and the people in the city do” (230d). We cannot learn anything from trees, comfortable as it may be to converse in their shade on a scorching summer’s day. What, then, is the point of dwelling on the plane tree, under which Socrates and Phaedrus will rest?
As is often the case in Plato, the explanation is as unexpected as it is ironic. A rhetorical trick has permitted Plato to insinuate himself into the dialogue without really taking part in it. To the Hellenic readers of the text it will have been obvious that the plane tree, platanos, is a semantic play on the author’s proper name, with both words derived from the Greek platys, meaning “broad.” (Plane trees that also lined the famous Platonic Academy in Athens are known to have remarkably broad leaves, as do all other sycamores. No wonder, then, that a variety known as “the London plane” predominates in New York City, with over 90,000 specimens scattered throughout the five boroughs.)
So, the irony is that Plato has literally overshadowed Socrates and Phaedrus, who lingered in the shade of a plane tree. The exaggerated modesty of a mere “reporter” of his teacher’s thoughts and great deeds turns out to be a rather thin veneer that hides the towering presence of the student over the Socratic legacy.
Besides, the mélange of the human and the plant, Plato and a plane tree, leads us to consider the ties that bind them in Platonic philosophy.
In what is surely the most remarkable statement of the plant-human relation in the history of Western thought, another Platonic dialogue, Timaeus portrays human beings as “heavenly plants”:
we declare that God has given to each of us, as his daemon, that kind of soul which is housed in the top of our body and which raises us — seeing that we are not an earthly but a heavenly plant — up from earth towards our kindred in the heaven. And herein we speak most truly; for it is by suspending our head and root from that region whence the substance of our soul first came that the divine power keeps upright our whole body (90a-b).
Now, this needs quite a bit of unpacking.
The contrast between the earthly and the heavenly plants is noteworthy because it, at once, shows how the two are similar to and different from each other. On the one hand, both are grouped under the heading ‘plant.’ Just this fact, in and of itself, should give plenty of food for thought! On the other hand, humans are so much spiritually higher than the highest of plants that the entire system of spatial coordinates (what is “up” and what is “down”) flips.
While our bodies may have a stake in the stuff of which other living beings are made, the substance of the rational soul derives from another region altogether: the eidetic sphere or the realm of Ideas. It is this superior realm that nourishes our psyches, attached to the soil of rationality as though by invisible roots.
In the earthly plant, the root is the lowest part immersed in the moist darkness of the earth. But in the heavenly plants that we are, the root is the highest and the most lucid point of our bodily constitution — the head, which is also closest to Ideas. Just as vegetation clings to the earth for support, so the heavenly plant stands upright and grows more vigorously the more it is bound to its own ethereal ground, namely rational thought.
We are, so to speak, topsy-turvy plants rooted at the head in the eidetic soil above us. Compared to this firm anchorage, our locomotion is as haphazard as the movement of tree limbs and branches flapping in the wind.
The image of a heavenly plant teaches us an important lesson about the nature of Platonic Ideas. Contrary to the everyday usage of the term, these are not found in our heads, even though the rational soul housed there has sprouted from the substance of which Ideas are made. Beauty, Goodness, Truth, and so forth are not to be conflated with beautiful, good, and true things, themselves the hazy reflections of corresponding Ideas.
Even if, in a terrifying thought experiment, all sensible reality were to disappear, Beauty, Goodness, and Truth, not to mention the Idea of a tree, would remain in their own autonomous sphere. This is because, eternal and immutable, Ideas exist independently of us, who pass like shadowy silhouettes over the face of the planet. In fact, they are the sole things that truly and fully are, neither coming into being nor passing away.
More stable than the earth itself, which is prone to landslides and earthquakes, Ideas form the cornerstone of Plato’s philosophy. Only by rooting ourselves in them, only by embracing the view of the human as a heavenly plant, can we hope to partake of the stability they signify.