Our knowledge is a receding mirage in an expanding desert of ignorance.

The line frames human understanding as inherently provisional: as we learn, we also become newly aware of how much remains unknown. The “mirage” metaphor suggests that certainty can feel close and vivid, yet recedes as inquiry advances—each answer opens further questions. The “expanding desert” reverses the common idea that knowledge steadily conquers ignorance; instead, the horizon of the unknown grows with the frontier of discovery. Attributed to Will Durant, the sentiment aligns with his popularizing view of history and philosophy as humbling disciplines, emphasizing intellectual modesty and the endlessness of inquiry.