Why did Karl Jaspers use the term Axial Age?

The German philosopher Karl Jaspers coined the term "Axial Age" to describe a pivotal era in human history, roughly spanning from 800 BCE to 200 BCE.1

He used this terminology to characterize a profound shift in human consciousness that occurred independently across various civilizations, including ancient Greece, India, Persia, and China. Jaspers observed that during this period, intellectual, philosophical, and religious systems underwent a fundamental transformation—a "turn," as if on an axis—moving away from localized, tradition-bound concerns toward [transcendence].1

This shift represented a move toward universal inquiry, where thinkers began to contemplate the nature of the cosmos, the ethics of "The Good," and the human relationship with the universe. By using the metaphor of an axis, Jaspers highlighted this era as the creative, ingenious foundation upon which subsequent human society and culture were built, marking a transition toward the global and universal concerns that continue to shape human self-perception today.1