POZZO
But he [Lucky] is dumb.
VLADIMIR
Dumb!
POZZO
Dumb. He can't even groan.
VLADIMIR
Dumb! Since when?
POZZO
(suddenly furious) Have you not done tormenting me with your accursed time! It's abominable! When! When! One day, is that not enough for you, one day he went dumb, one day I went blind, one day we'll go deaf, one day we were born, one day we shall die, the same day, the same second, is that not enough for you? (2.769-73)
Frustrated at his inability to understand time, Pozzo writes it off as irrelevant.
POZZO
(halting) You are human beings none the less. (He puts on his glasses.) As far as one can see. (He takes off his glasses.) Of the same species as myself. (He bursts into an enormous laugh.) Of the same species as Pozzo! Made in God's image! (1.314)
It could be that Pozzo finds this statement so amusing because he doesn’t consider himself human; he considers himself a god.
POZZO
He can no longer endure my presence. I am perhaps not particularly human, but who cares? (To Vladimir.) Think twice before you do anything rash. Suppose you go now while it is still day, for there is no denying it is still day. (They all look up at the sky.) Good. (They stop looking at the sky.) What happens in that case—(he takes the pipe out of his mouth, examines it)—I'm out—(he relights his pipe)—in that case—(puff)—in that case—(puff)—what happens in that case to your appointment with this . . . Godet . . . Godot . . . Godin . . . anyhow you see who I mean, who has your future in his hands . . . (pause) . . . at least your immediate future? (1.402)
Notice how Pozzo moves from talking about his not being human to a discussion of Godot. This basically invites a comparison of the two characters as divine figures (which we also discuss in the "Characters" section).