ESTRAGON
All the dead voices.
VLADIMIR
They make a noise like wings.
ESTRAGON
Like leaves.
VLADIMIR
Like sand.
ESTRAGON
Like leaves.
[…]
VLADIMIR
What do they say?
ESTRAGON
They talk about their lives.
VLADIMIR
To have lived is not enough for them.
ESTRAGON
They have to talk about it.
VLADIMIR
To be dead is not enough for them.
ESTRAGON
It is not sufficient. (2.98-114)
Vladimir and Estragon project their own dissatisfaction with their lives onto the noises they perceive as "dead voices." To live is insufficient, and so is to die; this leads right into Estragon’s earlier conclusion that to do neither is therefore the safest option. Of course, as the play demonstrates, this too is dissatisfying.
ESTRAGON
We don't manage too badly, eh Didi, between the two of us?
VLADIMIR
Yes yes. Come on, we'll try the left first.
ESTRAGON
We always find something, eh Didi, to give us the impression we exist?
VLADIMIR
(impatiently) Yes yes, we're magicians. (2.292-4)
Again, Vladimir is concerned solely with the boot while Estragon focuses on the larger issue at hand. He understands what thus far has been made clear only to the audience: that, unsure of how to be human, Vladimir and Estragon are forced to play-act, to pretend, to imitate what they think to be the normal course of human activity. It is through these affectations that the men "give [themselves] the impression [they] exist."
ESTRAGON
(aphoristic for once) We are all born mad. Some remain so.
[…]
VLADIMIR
I wouldn't go so far as that.
[…]
VLADIMIR
No, I mean so far as to assert that I was weak in the head when I came into the world. But that is not the question.
[…]
VLADIMIR
We wait. We are bored. (He throws up his hand.) No, don't protest, we are bored to death, there's no denying it. (2.536-545)
Vladimir isn’t concerned with his condition when he came into the world, but only his present condition. His conclusion that the only problem is boredom is ironic, since while he speaks he ignores the call to action spurred by Pozzo’s cries for help.