In a passage suffused with dramatic irony, Dmitri rejects the possibility that Fyodor was murdered by Smerdyakov:
“I don’t know who or what person, the hand of heaven or Satan, but … not Smerdyakov!” Mitya snapped out resolutely. “But why do you maintain so firmly and with such insistence that he is not the one?” “From conviction. Not from impression. Because Smerdyakov is a man of the most abject nature and a coward. Not just a coward, but a conjunction of all cowardice in the world taken together, walking on two legs. He was born of a chicken [...] He’s a sickly, epileptic, feebleminded chicken, who could be thrashed by an eight-year-old boy."
After Dmitri is arrested as a suspect in his father’s murder, Nikolai Parfenovich claims that Smerdyakov is also being investigated as a suspect. Fyodor mockingly dismisses this possibility, characterizing Smerdyakov, in hyperbolic terms, as not only a coward but “a conjunction of all cowardice in the world taken together, walking on two legs.” Dmitri, like the other members of his family, underestimates Smerdyakov. However, Smerdyakov is indeed the murderer, a fact known to the reader but not to Dmitri. There is a dark sense of comedy in this scene, as Dmitri further implicates himself in his mockery of the true killer.