Abstract

A leaf falls to the ground, wafting lazily on the afternoon breeze. Clouds move across the sky, and birds sing. Are these events governed by universal laws of nature, laws that apply everywhere without exception, subsuming events such as the falling of the leaf, the movement of the clouds and the singing of the birds? Are such laws part of a small set of fundamental laws, or descended from such a set, which govern everything there is in the world?