Participation in a genuine face-to-face conversation is not just waiting for your turn to speak. Active listening and genuine engagement are prerequisite.
A true conversation is engrossing and has a life of its own. We can never quite know in advance what will emerge as we allow ourselves carried along by the immanent logic of the subject matter. In a spirit of trust and sincerity we can lay open what Gadamer calls “our fore-structures of understanding.” We are likely to learn something when we are able to air and test our biases and prejudices in relative safety.
Incommensurability of viewpoints provides forward impetus and a certain creative tension. A conversation can remain a conversation if it takes a confrontational turn, but will break off if either participant resorts to strategic manipulation or an argumentative mode of speech. A true conversation can be measured by the extent of its maieutic productivity—the extent to which words are used as midwife.

The way one word follows another, with the conversation taking its own twists and reaching its own conclusion, may well be conducted in some way, but the partners conversing are far less the leaders than the led. No one knows in advance what will “come out” of a conversation. Understanding or its failure is like an event that happens to us.
The unpredictability of a true conversation lies in allowing oneself “to be conducted by the subject matter” (1997: 66). This does not mean keeping within the confines of the original topic. It is precisely the digressions, detours, tangents—and silences—which are the fruits of the immanent logic of the subject matter. Gadamer’s concept of “play” is important here. He asserts that the concept of playing a game—with its spirit of “buoyancy, freedom and the joy of success”:
is structurally related to the constitution of the dialogue with another person... it is no longer the will of the individual, holding itself back or exposing itself that is determinative rather, the law of the subject matter is at issue in the dialogue and elicits statement and counterstatement and in the end plays them into each other.
Gadamer’s “first condition of the art of conversation” is “ensuring that the other person is with us.” He speaks in terms of the “art of testing,” “questioning” and “lay[ing] open.” The creative element of a Gadamerian conversation can be characterized by “maieutic productivity... the art of using words as a midwife.” Specifically: it is the initially unseen but “immanent logic of the subject matter that is unfolded in the dialogue” (1994: 367-368).
Gadamer, Hans Georg (1994) Truth and Method. Second Revised Edition Revised translation by Joel Weinsheimer and Donald G. Marshall. New York: Continuum. (Originally published as Warheit und Methode, 1960.)