“Dialectic” is coined by Plato in order to describe the proper method of philosophy. Although it is used in various ways in Plato’s texts, dialectic always retains its relation to a conception of philosophy as a dialogue between a knowledgeable teacher and a learner.

The word “dialectic”

Plato introduces the term “dialectic” in philosophy. “διαλεκτική”, as a substantive noun, is derived from the feminine form of the adjective “διαλεκτικός”, an adjective that is not recorded before Plato either. It is harder to determine the origin of the terms “διάλεκτος” and “διάλογος”, though it cannot be ruled out that they are of Platonic coinage as well. In contrast, the verb “διαλέγομαι” (in the sense of discussing with somebody), the origin of all these new words, is very old.

Preplatonic dialectic

The second half of the fifth century BCE, the age of the Sophists and of Socrates, is the crucial period for the establishing of a new form for approaching philosophical problems through the exchange of questions and answers. The dogmatic way of presenting philosophical positions characterising the Presocratic period is gradually abandoned in favour of developing problems dialectically – such a shift is doubtlessly related to the emphasis on the techniques of persuasion required for participating in the democratic institutions of Athens. In his first writings Plato is anxiously trying to distinguish the Socratic way of discussing from the Sophistic practice of rhetoric; such effort indicates that the distinction was not obvious to his contemporaries. Aristophanes provides fair evidence of this by presenting Socrates in the Clouds as a sophist and painting a lively picture of the new method of philosophy, which was based on thoroughgoing discussions and investigations on definitions, deifying language, recognising the importance of persuasion and launching critique on established values.

Aristotle is said to have considered Zeno as the founder of dialectic, in the sense of introducing a method for investigating philosophical problems by presenting and refuting arguments. Thus, notwithstanding the Socratic and Sophistic turn, a certain part must have been played in establishing the dialectical method by the fecund way of thinking introduced by Parmenides and taken up by Zeno, Melissus and Gorgias. Moreover, it is important to note that the exchange of speeches is a structural feature of Athenian comedy and tragedy, while dialogues are also interjected by Herodotus and Thucydides in their narratives, when important ethical issues are discussed.

The use of dialectic in Plato’s dialogues

The dominant approach on this topic distinguishes three forms of dialectic in Plato’s works, corresponding to the three periods of his philosophy.

Period 1: Since the word “dialectic” is not recorded in the early dialogues, the Socratic “discussing” (διαλέγεσθαι) is defined in juxtaposition to Sophistic rhetoric or eristic. Contrary to the amoralism of the Sophists, who use various rhetorical strategies (epideictic speeches, controversy, poetical metaphors) in order to maximise the persuasion of their discourse, Socrates establishes a method of discussing ethical problems based on the search for universal definitions, on questions and short truthful replies (a simple yes or no, if possible), and on the so-called “έλεγχος”, the refutation of an interlocutor’s position on grounds of contradictory concessions made by the interlocutor himself.

Period 2: The negative Socratic dialectic is set aside in the middle dialogues, starting from the Meno, in favour of a consensual process of expounding philosophical issues and positions. The pinnacle of this transformation is located in the central books of the Republic, where dialectic comes to be nominalised and identified with philosophy, i.e. the apprehension of the Forms. Dialectic is a course of ascension carried out through the intellect alone and within the conceptual space of the Forms, comprehends the mathematical sciences and is concluded through the understanding of the unifying role of the transcendent Form of the Good.

Period 3: In the later dialogues, starting with the Phaedrus and carrying on with the Sophist, the Statesman and the Philebus, dialectic is identified with the method of “collection and division”, i.e. with an attempt to map the terrain of mutual relations between the Forms.

This picture, albeit not incorrect, is too schematic and rigid. As is usually the case with the developmental model, the distinction of three periods underestimates elements of continuity in Plato’s corpus. The “διαλέγεσθαι” of the early Socratic dialogues is made up of various elements, many of which are actively present throughout Plato’s works.

Unifying elements of Plato’s dialectic

Plato keeps referring to dialectic as an important element of his philosophy, even though the way philosophy is carried out varies significantly in his dialogues. This means that “διαλέγεσθαι” is a constitutive part of Plato’s conception of philosophy through and through. But dialogue was a common feature of all philosophical movements around the end of the fifth century BCE. Therefore, in spite of Plato’s copious efforts, the early dialogues fail to distinguish clearly Socrates’ method from the Sophists’ method. Controversy (αντιλογική), i.e. the exchange of philosophical arguments through questions and answers, as well as refutation (έλεγχος), seems to be a common legacy of their time. Besides, Socrates himself delivers long speeches at times or resorts to the mythological poetical tradition. If there is one thing distinguishing the Socratic-Platonic approach, it is the observation that exchanging arguments does not aim only at dialectical victory, but at “λόγω διδόναι και δέξασθαι”, i.e. at justifying through discourse and argument the way of life and the stance of the philosopher toward what is most important, justifying the essential cultivation of one’s soul.

“You strike me as not being aware that, whoever comes into close contact with Socrates and has any talk with him face to face, is bound to be led by the logos and to be unable to stop before giving an account of himself, of the manner in which he now leads his life, and of the kind of life he has lived hitherto” Laches 187e
“It is this sort of people we ought to imitate, the people who seek being together with each other and with themselves and exchange arguments while aiming for the truth and seeking the experience of one another” Protagoras 348a

Dialectic gradually turns into communion of souls. In the middle dialogues every form of aggressive disproving of the opponent’s position is put aside (every form of “eristic”,“controversy” or “refutation”) and the philosophical dialogue is carried out with the gentleness involved whenever friends are jointly investigating what is true. In the Republic the spectre of the rival-sophist has been finally removed. Dialectic is introduced in juxtaposition to the cognitive step preceding it, i.e. the mathematical sciences, and is the last cognitive stage in a course of increasing distancing from the senses – a movement of reason (λόγος) itself. An ascending course from Forms to the Form of the Good and once more a renewed descent to Forms, when the unifying dimension and the ontological priority of the Good has been apprehended. It is a placating process for the soul that “draws it from the barbaric slough” of the senses (533d). It is also “synoptic/comprehensive” (537c), i.e. able to make up the entire preceding cognitive course.

“[by the other section of the intelligible] I mean that which reason itself lays hold of by the power of διαλέγεσθαι, treating its assumptions not as beginnings but literally as hypotheses; as footings and springboards, so to speak, to enable it to rise to that which requires no assumption [ανυπόθετον] and is the starting-point of all, and after attaining to that again taking hold of the first dependencies from it, so to proceed downward to the conclusion, making no use at all of any object of sense but moving on through Forms, only with Forms, and ending with Forms” Republic 511b-c

The late dialogues retain all the main features of Plato’s dialectic. They are all directly dramatic, hence Plato is unable to interpose observations through a narrator. The methodological elements are now put forward and offered to the reader directly by the kind of dialogue itself, because it is carried out between a teacher and a student. Dialectic is a joint attempt to map the realm of the Forms. Moving from a more general Form to a more particular Form is called “division” and moving in the opposite direction is called “collection”. The dialectician, therefore, is the person who can collect and divide the Forms according to their true nature.

“One must know the truth about all the particular things of which he speaks or writes, and must acquire the ability of defining all things; then when he has defined them, he must know how to divide them until he reaches what cannot be divided further. One must also be able to understand the nature of the soul, must find out the form adapted to each soul’s nature, and must arrange and adorn his discourse accordingly: offering to the complex soul elaborate and harmonious discourses, and simple discourses to the simple soul. Only then can one artfully use the genus of discourses --in accordance to the art that suits one’s nature-- either for purposes of instruction or of persuasion, as has been revealed by our whole preceding discussion.” Phaedrus 277b-c

Author: Vassilis Kalfas
  • Dixsaut, Μ. Metamorphoses de la dialectiquedans les dialogues de Platon. Παρίσι, 2001.
  • Kerferd, G.B. The Sophistic Movement. Λονδίνο, 1981.
  • Nehamas, A, Virtues of Authenticity. Princeton, 1999.
  • Robinson, R. Plato’s Earlier Dialectic. Οξφόρδη, 1953.
  • Vlastos, G. Socrates. Ironist and Moral Philosopher. Cambridge, 1991.
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