"A hand among many hands stretched out across the centuries, bearing chisel and hammer to carve a passage thorugh the stone of our opinions, through the walls of what we call knowledge."
[Elvin Karda: With every moment of Wonder.]
Presenting an insight into Plato's philosophy in Politeia, The Republic.
Plato’s Politeia is not written as a systematic treatise, but as a philosophical dialogue. This form is by no means coincidental, but rather an expression of his view of how philosophical knowledge arises in the first place. Plato does not merely present philosophical teachings, but allows truth to emerge through shared conversation. In this way, the dialogue form differs fundamentally from mere instruction: it combines the knowledge that something is the case with the knowledge of how knowledge is acquired. The reader follows the process of knowledge formation themselves and is encouraged to understand it.
Socrates is at the centre of this process. Using maieutics, he guides his interlocutors to draw insights from their own reason, whilst elenctics serves to uncover and refute contradictory or untenable opinions. Philosophical knowledge thus arises not through authoritative instruction, but through the critical examination of convictions that appear self-evident. The dialogue form makes this process visible and, at the same time, clarifies the difference between mere opinion (doxa) and well-founded knowledge (episteme).
At the same time, the dialogue serves to examine various conceptions of justice step by step and to highlight their limitations. The interlocutors embody different ethical and political positions, which are not chosen at random. Kephalos represents the traditional, religiously influenced morality of ancient Athens and initially defines justice as truthfulness and the settling of debts. His son Polemarchos adopts this way of thinking and develops it further in the spirit of the Homeric tradition by asserting – following Simonides – that justice consists in doing good to friends and harming enemies. The transmission of these views from father to son illustrates how deeply traditional moral concepts are rooted in society. Socrates, on the other hand, breaks with this tradition by subjecting every position to rigorous dialectical scrutiny, thereby paving the way for a new, philosophically grounded conception of justice.
The refutation of Polemarchus’s definition serves as a prime example of the method of Socratic dialectic. Socrates first points out the epistemic problem that people can be mistaken about who is actually a friend or a foe, so that moral action must not be made dependent on subjective judgements. Furthermore, he highlights a moral problem: whoever harms another person corrupts their character and thereby ultimately increases injustice. Finally, he develops a virtue-logical argument: a virtue can never produce its own opposite. Just as warmth does not produce cold and music does not make anyone unmusical, neither can justice bring about injustice. This overcomes the traditional Homeric maxim whilst at the same time paving the way for Plato’s positive definition of justice.
However, Plato does not develop this directly in relation to the individual soul, but initially using the model of the state. The polis serves as a heuristic tool in this regard: what can be more easily observed within the broader context of the state can subsequently be applied to the more elusive order of the human soul. Since the soul itself is not directly visible, its structure is examined as reflected in the ideal state. In this way, Plato sets the stage for his central thesis: that justice, both in the state and in human beings, consists of a harmonious order of its individual parts.
Little (personal) introduction
Throughout my life I have encountered Plato’s Politeia time and again: at school, while preparing for university entrance examinations, during my legal studies, and now once more as in my philosophy studies. Each encounter left me with the impression that I understood the work more fully; yet each new reading revealed further layers beneath what I had previously taken to be understanding. Few books reward repeated study as generously as Plato’s Republic.
Hardly any other work combines questions of justice, the Good, knowledge, and opinion with comparable depth and sophistication. Although the dialogue is often read primarily as a political treatise, the virtues of the state and those of the soul mirror one another, allowing Plato to explore the conditions under which human beings may orient themselves toward the Good.
Particularly I am fascinated by the three famous allegories: the Sun, the Divided Line, and the Cave. Together they demonstrate that the Good cannot be adequately captured through definitions alone. Instead, Plato approaches it through images that guide the reader gradually toward philosophical insight. The Politeia is therefore not a textbook of ready-made answers, but an invitation to refine one’s own vision and to learn to distinguish appearance from reality, to sharpen one's one perspective.
This invitation becomes especially apparent in Plato’s epistemology. In Book V, as part of his characterisation of the philosopher, he develops the fundamental distinction between epistēmē and doxa—between knowledge and opinion. This remains the most detailed exposition of that distinction in his corpus and continues to provoke scholarly debate. Do knowledge and opinion differ primarily as modes of cognition, as objects of cognition, or in both respects simultaneously? Plato’s discussion suggests that the answer is far from straightforward.
What I find particularly remarkable is that opinion is not simply dismissed as error. It possesses its own sphere, its own legitimacy, and its own relation to reality. Likewise, knowledge is not presented as the mere accumulation of correct propositions. Even within the Politeia, one can discern different levels of cognition: discursive reasoning, which proceeds through concepts and arguments, and a higher form of insight directed toward that which grants permanence, intelligibility, and truth to all things. One of Plato’s greatest achievements, in my view, lies precisely in portraying knowledge not as a possession but as a process of intellectual and moral development.
The arising questions reach far beyond antiquity. What does it mean to know something? Under what conditions can knowledge be justified and communicated to others? Where does that deeper understanding begin which manifests itself less in propositions than in judgement, experience, or skill? Modern epistemology addresses such issues through distinctions between propositional and non-propositional knowledge, or between “knowing that” and “knowing how.”
Against this background, the Theory of Ideas appears in a particular light, it is not merely a metaphysical claim about a second world existing beyond the sensible realm. Rather, it is an attempt to explain how knowledge is possible at all and why our concepts can be more than arbitrary conventions. The Forms provide the standards by which thought is guided and evaluated. They explain why we can meaningfully distinguish between better and worse accounts of justice, virtue, or goodness.
In this respect, the Ideas fulfil three functions simultaneously: they ground the existence of things, their knowability, and their value. The Ideas are, by their very nature, existent, knowable, and good; sensible particulars possess these characteristics only in a derivative manner. Being, truth, and value converge within them. Consequently, the Good is not merely the absence of evil. It is a positive principle that calls human beings to realise and bring forth what is good.
This helps explain why Socrates repeatedly leads his interlocutors beyond their initially plausible definitions. He reveals how readily we mistake familiarity for understanding and invites us to seek more universal and robust conceptions of justice, virtue, and the Good. His method remains strikingly relevant. With sharp irony and relentless questioning, he dismantles established certainties, but not for the sake of destruction: In pursuit of deeper insight. The sophists, defenders of convention, and ambitious young men who populate the dialogue represent intellectual attitudes that remain familiar in every age.
It is precisely this interplay of epistemology, ontology, and ethics that makes the Politeia an inexhaustible work for me. It not only teaches us how to think about the world; it also challenges us to examine the foundations of our own thinking. Every reading reveals new connections, new tensions, and new questions. The dialogue does not simply provide doctrines to be accepted, but demands an ongoing engagement with the most fundamental questions of human existence.
For this reason, Plato’s Politeia continues to accompany me after many years of study. Each return to the text opens new perspectives and discloses new depths. The essays that follow bring together some of my reflections on this remarkable work. They make no claim to completeness. Rather, they mark a series of milestones along an intellectual journey that remains, and perhaps must remain, unfinished.
How is the Good recognised, and what is the nature of the knowledge of the Good?
The recognition of the Good and the question of the nature of this knowledge constitute one of the most difficult passages in Plato’s theory of knowledge. The classical philologist Thomas A. Szlezák, from whose circle of students the Tübinger Schule emerged, addresses this fundamental theme by highlighting several points simultaneously: Plato’s position and his critique of modern interpretations (and also how Aristotle understood the idea of the Good differently by identifying the Good with the One. This topic is also very interesting and we could think, if it is an interpretation of Aristotle or if there are predicates or premises leading to the conclusion of identifying the Highest Good with the Unmoved Mover, but let us discuss this some other time, some other place :* merci).
Let us turn to the question of wether and how the Good can be recognized.
If we were to assume that the Good could be recognised in the same way as an ordinary object, then we would recognise the Good just as we see a tree and recognise it as a tree. The Good would be an object alongside other objects, distinguishable and definable by its unique characteristics.
Socrates would reject this view, for according to "Politeia", the Good is, in fact, the very condition for the Good to be recognised at all. Here the allegory of the sun comes into play once more: although humans can see the sun, it is primarily the sun that makes it possible to see other things. Thus, the Good fulfils the same function as thought.
The opposing view, namely that the Good is entirely unknowable, assumes that if the Good is the prerequisite for all knowledge, it can never itself be known.
In contrast, Szelezák concedes that the Allegory of the Cave presupposes that the Good can be recognised; after all, the philosopher is able to ascend to the sun. “The fact that the Good can be recognised is the conclusion (517b8-c1) of the Allegory of the Cave and, in a certain sense, also its prerequisite, for without it the ascent would indeed not be worthwhile (as the cave-dwellers believe: 517a4); therefore, the knowability of the Good is already touched upon preparatorily in the Allegory of the Sun (508e3–4, analogous to the visibility of the sun 508b9–10). In the explanation of the Allegory of the Cave, we also learn that the soul ultimately even acquires the ability to ‘endure’ gazing upon the most luminous of all that exists (anaschesthai theômenê: 518c9–10). The fact that contemplating the Idea of the Good is possible ‘only for a few moments’ (Albert 1996, 153) is confirmed by this passage.”
How, then, can the Good be recognised?
Not as one recognises trees, nor as one defines them logically; the Good is grasped through dialectic. Several stages must be overcome, and the path begins with the recognition of individual good things, such as justice, courage and beauty. At the next stage, the question arises as to what actually makes all these things good. The individual good things are examined: one looks for commonalities and searches for a common ground. This process is what dialectic entails.
At the third stage, dialectic ascends ever higher, whilst elenctic refutes false opinions. Dialectic sees the reason behind the reason and keeps asking what this and that depends on, until finally nothing higher can be sought. Thus dialectic attains the Good and, with it, the highest idea in understanding.
“It therefore stands to reason that the prior act of beholding (theastai) or seeing the Good, as distinct from this, should be understood as a holistic, intuitive grasp which – like the sudden beholding of the Idea of the Beautiful in the Symposium (210e4) – consists of a single step: the unifying vision of the manifold into unity.”
In summary: The Good is knowable. Its cognition “therefore belongs to discursive thought”, whereby elenctic clears away false opinions and adopted everyday definitions, whilst dialectic prepares the way for cognition by ascending from individual ideas to the highest principle.
The actual act of recognition, however, could be a sudden glimpse (exápinas), as in the Symposium; but it can also emerge suddenly, as in the Allegory of the Cave, where the prisoner beholds a path as if from nowhere and unties himself, whilst increasingly realising the falsity of the images before stepping into the sunlight.
Plato’s Allegory of the Sun
The Allegory of the Sun occupies a central position within Plato’s Republic and is of fundamental importance for understanding his philosophy. Together with the Allegory of the Cave and the Allegory of the Lines, it forms the core of Plato’s theory of knowledge and his theory of ideas. These three allegories bring together the essential ideas of his philosophical system and present them in a vivid context.
The Sun Allegory becomes necessary because the Idea of the Good (unlike, for example, justice) cannot be directly defined or deduced. Plato therefore describes the path to knowledge by means of an analogy. The allegory not only aims to establish a hierarchical order between the image and the archetype, but is also intended to illustrate the fundamental structure of reality as a whole.
At the heart of the allegory lie two analogous propositions. Firstly, the Idea of the Good relates to the intellect in the same way as the sun relates to the sense of sight. Secondly, the Idea of the Good relates to the realm of the thinkable in the same way as the sun relates to the realm of the visible. This establishes a structural correspondence between the sensually perceptible world and the intelligible world.
Plato explains this using the example of sight: although sight and visible objects are related to one another, this relationship alone is not sufficient. A third element is required (light) for seeing and being seen to be possible at all. The light emanates from the sun, which itself belongs to the heavenly gods. The faculty of sight cannot therefore actualise itself by its own power, but is dependent on an external source. It is only through sunlight that visible things become truly recognisable. (There is also a sensible relation of nous: the mind's eye, way back before philosophers elevated the term to draw a line between pure intellect and the part of soul, which is recognizing universal truths. . . )
This epistemological (gnoseological) statement is complemented by an ontological one. The Sun and the Idea of the Good are not only principles of knowledge, but also principles of being. Thus, in the visible world, the sun enables the creation, growth and preservation of all life. Similarly, the Idea of the Good confers being and existence upon the intelligible world. The Good therefore stands even above being, as it is its actual cause.
In doing so, the sun does not merely fulfil the function of an element within an analogy of proportion, but assumes a mediating role. Unlike other visible things, it is not itself something produced, but rather the prerequisite for knowledge to take place at all. This also clarifies the relationship between the faculty of knowledge and the object of knowledge.
Plato further makes it clear that knowledge always depends on the nature of its object. If the soul turns towards the changeable and the obscure, this is akin to attempting to recognise a shadow in the dark. Reason, as it were, becomes mingled with the darkness and fails to attain certain knowledge. Only when it turns towards the unchanging and the intelligible can true knowledge arise.
The soul is not, however, confined exclusively to the intelligible world. It can direct itself both towards the realm of the unchanging and towards the realm of becoming and passing away. Depending on which sphere it turns to, it attains either mere opinion (doxa) or true knowledge (episteme).
The Sun Allegory is also regarded as the simplest of the three great allegories. It first summarises the theory of ideas in a fundamental form and illustrates the concept of two hierarchically ordered worlds, which are linked by a relationship of analogy. The different forms of knowledge (in particular opinion and knowledge) are first hinted at. These distinctions are then elaborated in greater detail in the Allegory of the Lines, whilst the Allegory of the Cave ultimately illustrates humanity’s ascent from ignorance to the knowledge of the Good.
Commentary on the Allegory of the Cave
The Allegory of the Cave forms the climax of the three famous allegories in Plato’s "Politeia".
Whilst the Allegory of the Sun describes the Idea of the Good and the Allegory of the Lines describes the various stages of knowledge, the Allegory of the Cave illustrates humanity’s journey from ignorance to knowledge. It deals with human nature in terms of education and ignorance, whilst at the same time highlighting the political and ethical role of the philosopher.
The cave is, first and foremost, a metaphor for ordinary human existence. The prisoners have been chained in one place since childhood. They can move neither their bodies nor their heads and see nothing but the cave wall in front of them. Behind them a fire burns; between the fire and the prisoners runs a path along which people carry objects. The prisoners, however, do not see these objects themselves, but only their shadows on the wall. Since they have never perceived anything else, they regard the shadows as the actual reality. Whoever recognises, names and explains the shadows most quickly is considered particularly wise.
Here, Plato criticises a form of knowledge that is limited to mere opinions and appearances. The shadows are merely images of images, projections of an already imperfect reality. The bearers of the objects can be understood as symbols of the Sophists, who, whilst conveying opinions and beliefs, do not lead people to the truth. The cave-dwellers confuse appearance with reality and regard their limited perspective as the whole of reality.
The moment of liberation is decisive. One of the prisoners is unchained and forced to stand up. This step alone is painful. He must turn his head, face the light and begin the arduous ascent out of the cave. Plato emphasises that knowledge is not a comfortable experience. Anyone who abandons their previous world view initially experiences confusion. The new seems less real than the familiar. Only gradually do the eyes become accustomed to the light.
Outside the cave, the liberated individual gradually recognises the true order of things. At first he sees shadows, then reflections, and finally the objects themselves. In the end, they even gaze upon the sun. In the Allegory of the Cave, this sun corresponds to the Form of the Good, the highest principle of knowledge of all. Just as the sun illuminates visible things, the Form of the Good makes true knowledge possible in the first place. The ascent from the cave is therefore not merely a gain in knowledge, but a transformation of the entire soul.
Plato describes this process as the ‘art of reorientation’. For him, education does not mean implanting knowledge into an empty soul, as one might implant eyes into a blind person. Rather, the soul already possesses the capacity for knowledge; it merely needs to be turned away from transitory things and directed towards Being. In 518d, Plato therefore describes education as the turning of the whole soul from becoming towards Being.
It is noteworthy, however, that the philosopher must not remain outside the cave. Although he has recognised true reality and the affairs of the cave now seem trivial to him, he is obliged to return. This reveals the political dimension of the allegory. The philosopher owes his education to the polis and must not use the knowledge he has gained solely for his own benefit. He must serve other people and endeavour to lead them to the truth as well.
It is precisely this descent that proves difficult and dangerous. Anyone returning from the bright sunlight into the darkness initially sees less clearly than the others. The cave-dwellers interpret this as proof that the ascent is harmful. They mock the returnee and would even kill anyone who sought to dissuade them from their familiar beliefs. Many commentators see in this an allusion to the fate of Socrates, who was sentenced to death by the Athenians because of his uncomfortable questions.
The Allegory of the Cave thus shows that knowledge is always a laborious process of self-transformation. It describes the path from opinion to knowledge, from appearance to reality, and from ignorance to enlightenment. At the same time, Plato makes it clear that true knowledge entails an ethical obligation. Those who have recognised the Good must not retreat into the solitude of truth. They must embark on the perilous journey back to humanity in order to help others lead a better and more just life. In doing so, Plato unites epistemology, pedagogy and politics into a single philosophical vision.
With every moment of wonder, my life grows
(A Song of Praise dedicated to the Phenomena of Wondering)
With that first sense of wonder, the world unfolds before me – not as an answer, but as the door to a hidden realm.
What we thought we knew crumbles before our eyes or vanishes
like a shadow the moment the sun shines.
The sky extends deeper than the eye can see, and every word already carries a fragrance of its meaning.
With every moment of wonder, I realise that I possess no knowledge.
Indeed, I do not even know how little I know.
The only thing I am sure of knowing is that I seek knowledge, and that with every step I take towards it, it eludes me once more.
And sometimes I wait, like a foolish bride on her wedding bed,
in the hope that my illusion might once again cast itself into my arms. But I come crashing down onto the hard ground of ignorance, and once again the hand of a thought pulls me up.
A hand among many hands stretched out across the centuries, bearing chisel and hammer to carve a passage thorugh the stone of our opinions, through the walls of what we call knowledge.
These are thinkers who inspire us not to let the conversation within us fall silent.
For in the dialogue of solitude, I am not alone, but two within one.
Only when I am at one with myself can I be with others.
Only by living with myself can I live with others.
And whilst my heart beats in unison with the vast blue expanse, I shall not rest until I have grasped and clarified, rescued the pure from the mire, tirelessly spun something warming even from the dust, and wrested an eternal meaning even from the transitory.
Perhaps the most beautiful things in life have no end, and perhaps we can never attain the highest insight, maybe it shall not be ours to possess, but we can understand the journey towards it as a pilgrimage. Every step is both arrival and departure, every horizon conceals another horizon beyond. And as the stars pulse above me, I behold your eyes once more, and the sense of wonder begins anew and my life grows.
Books I read and used (not ordered):
Platon: Politeia
Wolfgang Wieland: Platon und die Formen des Wissens
Herwig Görgemann: Platon
Joachim Lege: Politeia - Ein Abenteuer mit Platon
Hannah Arendt: Sokrates - Apologie der Pluralität.