In his seventh letter (if indeed it is his), Plato remarks that he will never write about the deepest matters of philosophy, ‘For this knowledge is not something that can be put into words like other sciences; but after long-continued intercourse between teacher and pupil, in joint pursuit of the subject, suddenly, like light flashing forth when a fire is kindled, it is born in the soul and straightway nourishes itself’ (341c). This idea, that there are some matters that cannot be expressed or attained to outside of oral dialogue, forms the backdrop to Dimitri Nikulin's book, Dialectic and Dialogue, which attempts to provide a philosophical and historical account of the origins, interrelatedness, and significance of dialectic and dialogue.

In the first chapter on the platonic origins of dialogue and dialectic, Nikulin identifies a development that is key to understanding the relation between them: ‘dialectic originally was an oral practice established in oral dialogue; written dialogue then appeared as an imitation of oral dialectic; and finally, written dialectic was distilled into a non-dialogical and universal method of reasoning’ (p. 2).

In chapter two, ‘Dialectic: Via Antiqua’, Nikulin looks in more detail at the origins of dialectic. For Plato, the purpose of dialectic is to know the ‘what’ of a thing (its essence). In Plato's earlier dialogues, Socratic oral dialogue forces its ‘interlocutors to recognize that the original description of a thing's essence was wrong and that they must begin anew, doing so often without success’ (p. 25). Plato develops dialectic as a discursive, logical activity: ‘dialectical investigation begins with what interlocutors can agree on and then proceeds toward a conclusion by excluding possibilities through reasoning with respect to opposites’ (p. 27). Aristotle takes dialectic in a different direction. In the Topics it is associated with premises that are probably true and is therefore distinct from both eristic dialectic and syllogistic deduction. It cannot be the case for Aristotle that dialectic is a science of being, since it concerns the probable and not the true. Thus, ‘Plato and Aristotle substantially disagree about what dialectic is and how far it extends’ (p. 43).

According to chapter three, ‘Dialectic: Via Moderna’, in modernity dialectic becomes ‘a logical calculus of propositions … taking mathematics as a paradigmatic example of clarity, systematicity, and order of arrangement’ (p. 49). Dialectic becomes one of reason's pretensions and needs to be subjected to critique: Kant's ‘transcendental dialectic is the critique of the rational illusion and unjustified claim of reason of achieving complete and absolute knowledge’ (p. 52). Nikulin traces the origins of Hegelian dialectic in Nicholas of Cusa's ‘program based on the coincidence of opposites’ (p. 54). For Hegel dialectic ‘utterly dissociates itself from dialogue and becomes the method and driving force that cannot be divorced from philosophy as the enterprise of solitary thinking’ (p. 65)

In chapter four, ‘Dialogue: A Systematic Outlook’, Nikulin identifies four key features of dialogue: personal other – the indefinable constant in and precondition for dialogue; voice – that which expresses and communicates discursively; unfinalizability – at every moment meaningful and always able to be carried further inexhaustibly; and allosensus – constructive, non-confrontational disagreement. Thus, dialogue ‘is a process of meaningful but unfinalizable allosensual exchange that can always be carried on without repetition of its content and that implies communication with other persons in the vocal expression of one's own (but not “owned”) personal other’ (p. 79). Dialectic, on the other hand, does not recognize this personal voice. It is monological. Moreover, it is not ‘unfinalizable’. It possesses the argument in a finite number of steps following formal logical rules, ending in a true conclusion, whereas dialogue only ‘accidentally’ reaches a logically justified conclusion.

In chapter five, ‘Dialogue: Interruption’, Nikulin considers the claim that ‘dialogue is essentially based on interruption’ (p. 95). It is this spontaneity of the interruption that distinguishes it from dialectic and written dialogue. In oral dialogue ‘there is no rule indicating when to interrupt or what to say exactly’ (p. 100). However, Nikulin's assertion, that to be ‘interrupted is to be included, invited, and recognized’ (p. 103), can hardly be said to reflect the common experience of being interrupted.

Nikulin, aware of the irony involved, gives the title ‘Against Writing’ to chapter six. He recognises that dialectical reasoning requires the written form to maintain its argument: ‘writing is more effective than human memory at storing lengthy lists and the exact details and particular path of an argument through which discursive thinking had to proceed in order to establish a proof’ (p. 120). However, writing's function as a ‘cure’ for the weakness of memory – verba volent, scripta manent – is not as successful as we might think. Writing conveys knowledge without understanding. It is inflexible. It cannot speak to defend itself or clarify its meaning. It cannot interrupt. And ‘if Plato is right in holding that being cannot be known discursively … then it cannot be approached through a step-by-step dialectical movement or argumentation, and it cannot be properly represented, written down, or read’ (p. 130).

This is an eloquent book, more rhetoric than dialectic, and its eloquence at times pushes the argument in unwarranted directions. Nikulin gives no consideration to the liberating nature of the written word, which makes available to all, potentially at least, the knowledge, skills, and techniques that are otherwise available only to a small elite. (The symposium is after all only open to a handful of invitees, ‘no fewer than the number of the Graces and no more than the number of the Muses’ (p. 83).) Nor does Nikulin consider the role of the electronic media as an alternative means of capturing and conveying oral dialogue. He also understates the major limitation of the oral, its fleeting nature. The dialogue must end, and once it is ended it disappears (unless captured on media such as YouTube). Oral dialogue may never be completed, but, unfinalizable or not, it will eventually be abandoned and lost.

Nikulin ends his book with a statement reminiscent of Martin Buber's ‘Dialogphilosophie’: ‘to be is to be in dialogue’ (p. 155). To be in dialogue with God? That is not a question the author considers or perhaps would want us to consider. But it is, I think, where his ‘conclusion’ is pointing.