From the secrets of nature to secrets of state, and from the mystery of the other to mysteries of the self, we ceaselessly probe the boundaries of our knowledge, ever aware that to push them yet further can empower us or even destroy us. The dangers—and the allure—of our inquiries into the hidden and the forbidden remain an enduring theme in drama and in novels, in philosophy and in science, in religious thought and in poetry, in music and in film. Should there be constraints on our knowledge, or limits to the power it brings us? These questions haunt our aspirations to know and to control, overshadowing the seeker of knowledge—whether Eve or Frankenstein, the philosopher who challenges our deepest convictions, or the scientist whose discoveries cannot be ignored or outrun. Through both story and sustained argument, and from The Odyssey to The Road, we will examine how the moral, social, and psychological costs of our pursuit of knowledge are assessed and engaged, and just how boldly we might dare to know.