Williams's precipitates Brick's revelation through a device introduced earlier, the off-stage telephone. Here the phone call is a call from the dead, evoking Skipper's final confession to his friend. As Brick confesses, he refused him. Thus Daddy delivers his final diagnosis, that Brick is disgusted with his own mendacity. He dug his friend's grave rather than face the truth, a truth that even now Brick would assign exclusively to Skipper.
While Daddy's diagnosis rings true, it also sounds suspiciously familiar. In some sense, it is almost one of those pat conclusions against which Williams warns in the stage notes. Though Daddy certainly plays judge here, he does not speak from an "objective" position, from the position according to which we can determine the "moral" of the play. His diagnosis is also implicated in the psychological drama unfolding before us. It does not speak from some place outside the play, commenting impartially on the action.
Thus note how Daddy's diagnosis strangely repeats his own remark to himself in Act II, where he murmurs in disgust over the mendacity in his staying with Big Mama for forty years. Here he projects this disgust onto his son:"You!" he cries accusingly. Already we have noted the numerous manifestations of Daddy's narcissistic investment in his son. Their final exchange makes explicit the men's mirror relation and particular through the complementary interplay of the "you"s and "me"s they find themselves screaming throughout this scene.
Thus Brick matches the revelation of his repressed desire with that of Daddy's death. Here the telephone almost embodies and voices Daddy's inner protest: "no, no, you got it all wrong! Upside down! Are you crazy?" The screeching child interrupts anew, both marking the violent revelation of the repressed and symbolizing Daddy's death itself. Daddy bellows in rage, denouncing the "lying dying liars" that surround him. The bawling child serves as another ventriloquism of his anguish.
Thus father and son figure as doubles in their roles as revealer and recipient of the other's inadmissible thing. Like Daddy's sojourn in "death's country," Brick's being "almost not alive" makes him "accidentally truthful." They present themselves as the only ones in the cast who have never lied to each other. Both stand on polar limits of the system of mendacity that is life. Note here how Brick's pronouncement on mendacity also echoes Daddy's, Brick being the drunkard and Daddy the dead man.
In telling Daddy of his death, Brick has staged a reversal, turned things "upside down," and now Daddy stands in the place he just occupied. It is a violent act, robbing Daddy of his second life. As Brick almost gratuitously declares upon his second exit, emphasizing the duality of the exchange that has just ensued: "You told me! I told you!"