What is Time?

What is time? Just like everything else in the world, our understanding of time has changed continually over time. This article tracks this question through the history of Western philosophy and looks at major answers from the likes of Aristotle, Kant, and McTaggart.

The human mind has long grappled with the elusive nature of time: what it is, how to record it, how it regulates life, and whether it exists as a fundamental building block of the universe. This timeline traces our evolving understanding of time through a history of observations in culture, physics, timekeeping and biology.