The central theme of “An Obstacle” is overcoming prejudice. This process is figuratively represented through the personification, gendering, and depersonalization of “Prejudice” (Line 11). Perkins Gilman’s use of capitalization and the male pronouns “he”/”him” (Lines 13, 14, 15, etc.) initially turns the concept into a large man. This man’s size is repeatedly emphasized; he sits “all across the road” (Line 12) and is described as “huge and high” (Line 14). Perkins Gilman highlights the masculine and overwhelming nature of prejudice with this characterization. The obstacle seems insurmountable—especially to a woman “with many things to do” (Line 2) climbing upward on a mountain (of life, tasks, or a literal peak).

Further, the speaker’s characterization of prejudice includes personality traits—specifically stubbornness. He is compared to a “colossal mule” (Line 20): an animal invoked to describe something incredibly stubborn. While mules are generally not known for their size, prejudice is, “colossal” (Line 20), or an unusually large mule, connecting the descriptions of prejudice’s large presence with his temperament. Building upon this, prejudice’s stubbornness is born from malice: The speaker says he has an “obdurate ill-will” (Line 34). Standing in the way is not just a mulish act—prejudice is an extremely large, immovable obstacle who is bitter and mean.