I never fully realized the perilous state of the humanities until I read recent remarks by physicists about “Plato’s cave”, one of the oldest and most influential allegories in Western literature. It appears in Plato’s book The Republic, which was written in about 380 BC. In the book, Plato recounts an extended conversation between his teacher, Socrates, and a group of Athenian youths on the nature of justice. Socrates regards education as vital to justice, and at the thematic core of The Republic likens the process of education to an escape from a cave.

Several physicists have recently given their own take on the meaning of this allegory. The Italian physicist Carlo Rovelli mentions it at the beginning of Reality Is Not What It Seems (Penguin 2016), describing scientific thinking – or the fashioning of “novel and more effective images of the world” – as the right way to escape the cave. Meanwhile, in The Greatest Story Ever Told – So Far: Why Are We Here? (Simon and Schuster 2017), US cosmologist Lawrence Krauss says that “Plato’s vision of ‘pure thought’ has been replaced by the scientific method”, which uncovers “the underlying realities of the world”.

So what’s the harm in stretching one’s interpretation of a book written almost 2500 years ago? A lot.

Not what it seems

The allegory – as told originally in The Republic – unfolds as follows. Imagine a cave, Socrates asks his companions, in which a community of people are chained in place so they face a wall, and are captivated by the images they see on it. The process of education unfolds in three steps.

In step one, individuals break free of the bonds and are able to turn around and see that the images are just shadows cast by other objects that a cohort of people are moving back and forth in front of a fire. Today’s teachers often compare that situation to a cinema, in which members of the audience, who have spent their lives thinking that cinema is reality, finally stand up and discover that movies are actually made by filmmakers who selectively display things for the entertainment and control of the masses.

In step two, an individual is dragged up a “rough, steep” path out of the cave and into the light. There, after acclimatization, that individual can see the eternal and unchanging ideas or forms that govern life in that cave. In this second step, the central idea (and hardest to grasp) is the Good, which Socrates compares to the Sun insofar as the Good illuminates and nurtures everything else. Later in The Republic, Socrates illustrates the relation between the ideas seen in the second step and particular examples by pointing out that while there are many beds there is a single concept “bed”, and knowledge involves grasping the concept in the examples.

But the bed example is just a teaching analogy. The ideas that occupy Socrates all have to do with human life, such as justice, truth, knowledge, love and courage. These ideas cannot be disproven or altered but are always at work, however dimly and inadequately, in cave activity. Understanding them is not becoming knowledgeable about, say, cosmology but becoming wise through a process of self-transformation in which one becomes able to be governed by the Good.

Remember it’s only an allegory: Socrates is playing a teacher’s role in trying to motivate Athenian youths, and the story aims to entice them to make the difficult journey up that rugged path. No deep reading is required to see that, in practice, education is a lifelong and never complete process. Thanks to our bodies and our mortality, humans never make it entirely out of the cave, which is their permanent home. Furthermore, there’s a third step in which the educated person, who is aware of the ideas, does not remain contemplating them, but attempts to use the acquired wisdom to interact with the other cave dwellers by returning into the cave.

And there’s another thing too: while the allegory is about education, Plato clearly means it to highlight the obstacles to education as well. One comes from an obsession with spectacle (think of the Internet and social media), which blocks the search for deeper truth. Another comes from powerful individuals who feel threatened by education and expertise, and try to quash them.

My problem with Rovelli and Krauss is their claim that science is the only mechanism to escape the cave and fulfill the educational process described by Socrates. This promotes a distorted and dangerous view of education. It bleaches from the realm of underlying reality anything that has to do with human existence. Socrates was interested in answering the question, “How should we human beings live?” and such an interpretation erases everything he cared about.

The critical point

In the cave, human beings have many different ways of living in which they seek love, prestige, pleasure, friendship, happiness and other kinds of “good” things, and the humanities seek to foster the wisdom that enables living well. Explaining the physical world – producing “effective images” of it – is only one of these ways. While the resulting images may help with other ways of living, they do not supplant them. To suggest that the scientific method replaces other ways of thinking and is the sole way to uncover underlying realities of the world not only fails to understand the cave allegory but also belittles the values and practices of the humanities.

These values include not only understanding ideas like justice but also things like Plato’s cave allegory. Calling science the way to escape Plato’s cave is an invalid interpretation – a dangerous one that attacks the humanities and wisdom they seek to foster. That, to me, is the most extreme hazard.

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