The fundamental nature of time is change. In physics and philosophy alike, the concept of suggests that no state—joyous or painful—is static.
Life is a series of peaks and valleys. While the "peaks" are celebrated, it is the "valleys"—the periods of hardship, loss, and uncertainty—that define human character. The adage "Tough times never last, but tough people do" (popularized by Dr. Robert Schuller) serves as a foundational principle in the study of psychological resilience. Tough Times Never Last
Tough Times Never Last: The Psychology and Practice of Resilience The fundamental nature of time is change