Man only likes to count his troubles; he doesn't calculate his happiness.

The line points to a psychological asymmetry: people readily inventory pain, injustice, and deprivation, yet rarely perform the same careful accounting of what is going well. Dostoyevsky often dramatizes how self-consciousness can turn into grievance—how the mind clings to suffering because it feels more “real,” more morally weighty, or more narratively satisfying than ordinary contentment. The remark also implies that happiness is frequently unrecognized while it is present; it becomes visible only in retrospect, after it has been lost. As a moral observation, it warns that fixation on troubles can distort one’s sense of life’s balance, making existence seem harsher than it is and encouraging resentment rather than gratitude.