“Invictus” celebrates something called the human spirit, a radical concept for Henley’s staid Victorian readership. It is a philosophical concept summarized in the word “yet.” “Yet” was something of a rare concept in 19th-century England. After all, within the established Christian vision, a person rose—or fell—only to offer gratitude to the Divine Creator. The soul was a gift from that same God and, whatever events defined life, it was destined for immortality, at once a part of and apart from each person.

Within the complex vision of the emerging sciences, any individual human—whatever the circumstances of their life—scraped to survive only because a species refuses to accept as logical its own extinction. For Henley, there was something else, something immeasurable, something not a gift but a something each person is born with, a something that demonstrates stoic endurance when tested by the most difficult circumstances, a something that is grander, larger, and more heroic than animal survival. The poem offers a view of the world that is pessimistic, a world “black as the pit from pole to pole” (Line 2), a world where much happens to people that people cannot control.

Yet—there is the word—yet individuals refuse to surrender to the suffering, refuse to bend, not because of the longshot premise of some vague, mythic afterlife, not because of some stubborn species need for persistence, but because that test brings out a person’s individual spirit.