Mulligan's "gaily" uttered phrase, "The mockery of it," expresses the liberating spirit of irreverence that pervades Ulysses. But nothing is at risk in Mulligan's mockery: he is a man to whom nothing is sacred, which makes him a heretic in Stephen's symbolic economy. The book's humor is more complicated, and more affirming of human dignity. Ulysses addresses its most serious concerns in what Ithaca calls a "jocoserious" manner.
On topic after topic—Christianity, epic heroism, Theosophy, Irish nationalism, and on and on—the novel mercilessly mocks received verities while reserving some serious interest in their claims. One might say that it preserves those parts of received teachings which can survive its delight in goring sacred cows.