Every conversation is a Prisoner's Dilemma scenario.
"Cooperate" is to treat your conversation partner as acting in good faith, seeking truth and not trying to exploit you.
"Defect" is to treat them as acting in bad faith.
Most conversations end in Cooperate-Cooperate, because most conversations have low stakes. When we discuss something trivial, like the weather or what we did today, we rarely assume the other person will take advantage of us. Sometimes, when discussing a difficult topic, we can both really learn something if we treat the other person like they have something useful to say. Both sides gain.
Sometimes, it's Cooperate-Defect. Either we treat the other person well and they take advantage of our kindness, or the reverse. The Defector wins, often by making bad arguments that sound good on the surface or strategically committing logical fallacies.
Often we end in Defect-Defect. Neither side tries to understand or internalize the arguments of the other because they assume the other will Defect. As in ordinary one-shot Prisoner's Dilemmas, this is a rational attractor solution that ends badly for both.
In the ordinary PD, playing tit-for-tat in repeated interactions can move the equilibrium point towards Cooperate-Cooperate. In conversation, it's harder: you never get to know for sure whether your conversation partner was Cooperating or Defecting in the last round (at least, it's very difficult and subject to bias). You can only guess, and if you start guessing that they will Defect then you're likely to move back towards the worse equilibrium.
Let it be known: I Cooperate in the Prisoner's Dilemma.