Several times throughout The Brothers Karamazov, Dostoevsky mentions left-handedness or the left side: schoolboys pick on Ilyusha for his left-handedness, Lyagavy strokes his beard with his left hand before preparing to cheat someone in business, and Grigory Vasilievich imagines that the door leading to the garden, which is on the left side of Fyodor Pavlovich’s house, was opened by Dmitri Fyodorovich, thereby providing further testimony that Fyodor’s eldest son murdered him in a fit of rage. Historically, the left side is a symbol of evil. The superstition that left-handedness connotes wickedness comes from the Bible. In Matthew 25:41, Christ sits on the throne of his glory and separates the righteous, who are on his right hand, from those who shunned him in life, who are on his left hand. He tells the latter to depart from him and sends them to hell, while the righteous go to paradise.
In The Brothers Karamazov, however, Dostoevsky undermines this left-side superstition and uses it to symbolize the human impulse to condemn others on arbitrary grounds. For instance, the author reveals how Kolya Krasotkin manipulated Ilyusha during their friendship, thereby providing a context for his stabbing Kolya with a penknife. Smerdyakov later tells Ivan Fyodorovich that the door to the garden was never open, and that Grigory is too stubborn to rethink his testimony against Dmitri. Finally, it’s ironic that Fyodor Pavlovich characterizes Lyagavy as a “scoundrel” and a cheat, given his own history of miserliness and crude behavior. Dostoevsky ultimately suggests that the tendency to explain away evil with something as arbitrary as left-handedness gives those who don’t share the trait an excuse to condemn others without examining their own behavior.