Of all the laughs that strictly speaking are not laughs, but modes of ululation, only three I think need detain us, I mean the bitter, the hollow and the mirthless. They correspond to successive… how shall I say successive… suc… successive excoriations of the understanding, and the passage from the one to the other is the passage from the lesser to the greater, from the lower to the higher, from the outer to the inner, from the gross to the fine, from the matter to the form. The laugh that now is mirthless once was hollow, the laugh that once was hollow once was bitter. And the laugh that once was bitter? Eyewater, Mr. Watt, eyewater. But do not let us waste our time with that. . . . The bitter, the hollow and—Haw! Haw!— the mirthless. The bitter laugh laughs at that which is not good, it is the ethical laugh. The hollow laugh laughs at that which is not true, it is the intellectual laugh. Not good! Not true! Well well. But the mirthless laugh is the dianoetic laugh, down the snout—Haw!—so. It is the laugh of laughs, the risus purus, the laugh laughing at the laugh, the beholding, the saluting of the highest joke, in a word the laugh that laughs—silence please—at that which is unhappy.
– Beckett, Watt