Emily Dickinson’s speaker reveals one of the poem’s main themes when they state, “Much Madness is most divine Sense” (Line 1). They pit senselessness versus sensibleness and argue that “the Majority” (Line 4) will “prevail” (Line 5) in determining what qualifies as rational and irrational. If a person adheres to the majority’s views, they “are sane” (Line 6) and acquire acceptance. A person who doesn’t subscribe to the edicts of the multitude becomes “straightway dangerous" (Line 7) and faces the punishment of “a Chain” (Line 8).

The image of the chain subverts the sensibleness of the majority and adds a layer of irony to the theme. A calm majority presumably wouldn't be fazed by someone who thinks and acts differently. Ideally, a composed majority would have confidence in their way of life and not feel threatened by the nonconformist. The harsh reaction to the nonconformist indicates that “madness” is a part of the majority. Their thirst for retribution is not sensible: It’s cruel and base.

The speaker doesn’t undercut their claim that sense lies with the person who stands out. Thus, the nonconformist’s “discerning Eye” (Line 2) stays judicious. Yet the route to the “discerning Eye” remains unclear. The reader might wonder how a person can cultivate a “discerning Eye,” and, as Dickinson’s speaker doesn’t elaborate, the best one can do is speculate.