ESTRAGON
(his mouth full, vacuously) We're not tied?
VLADIMIR
I don't hear a word you're saying.
ESTRAGON
(chews, swallows) I'm asking you if we're tied.
VLADIMIR
Tied?
ESTRAGON
Ti-ed.
VLADIMIR
How do you mean tied?
ESTRAGON
Down.
VLADIMIR
But to whom? By whom?
ESTRAGON
To your man.
VLADIMIR
To Godot? Tied to Godot! What an idea! No question of it. (Pause.) For the moment. (1.266-275)
The verb "tied" makes more explicit the similarity of these two men to Lucky, who is literally tied by the rope around his neck. Estragon is actually asking the same question we just did—whether or not they are made prisoners by Godot. Vladimir, of course, is unable to answer with any certainty. Interestingly, it is his very uncertainty that makes him a prisoner of his own inaction.
ESTRAGON
I'm unhappy.
VLADIMIR
Not really! Since when?
ESTRAGON
I'd forgotten. (1.766-8)
Waiting for Godot argues that suffering is the constant and eternal condition of man.
ESTRAGON
What about hanging ourselves?
VLADIMIR
Hmm. It'd give us an erection.
ESTRAGON
(highly excited) An erection!
[…]
ESTRAGON
Let's hang ourselves immediately! (1.170-4)
The appeal of hanging isn’t that it would bring death, but rather that it’s something to do during the eternal wait. The men are unable to comprehend the consequence of such an action.