W. B. Yeats's poem “The Second Coming” presents a horrifying scene. The world is spinning out of control like a falcon who can no longer hear its master. Everything is falling apart, descending into anarchy. Evil is intense. Good appears weak and without conviction.

The speaker feels as if “some revelation is at hand.” The Second Coming must be approaching, he thinks. Then he has a vision, “a vast image out of Spiritus Mundi.” The Latin words spiritus mundi literally mean “spirit of the world,” and they refer to the collective consciousness or spirit of all humankind. But this Spiritus Mundi is not spawning something good and beautiful. Rather, the speaker sees a horrible monster crouching and crawling across the desert. It represents the antichrist.

Notice what the speaker is implying here. The antichrist will come out of the collective spirit of humanity. People have become so corrupt that they as a group will spawn this monstrous creature, this nightmare, that will actually try to present itself to the world as Christ. The Spiritus Mundi has lost its way, its focus. It no longer follows the Spirit of God. Rather, it has given in to evil, perhaps even become evil itself, so much so that out of it will arrive the “rough beast” that will announce the imminent end of the world.