How does the universe work? It's been one of the great nagging questions for our species. For millennia, for many of us, it's been at the back of our minds. We've thought and thought about it, and have come up with all sorts of exotic explanations. A few thousand years ago, when cities and culture rose to support a more idle class, we began to think about the question in earnest and we started to get real answers.
Physics in Antiquity
The study of the natural world in antiquity was deeply connected with philosophy. At the time, few measurement devices had been invented, so it was nearly impossible to test hypotheses. Essentially, if the idea looked good, and most people concurred, it was adopted as the truth. The early physics, or natural philosophy was an advanced form of navel-gazing.
Ancient Greece, India, and China all contributed to the roots of physics, but the contributions of Greece are most well known. The names of Aristotle and Ptolemy are famous for their contributions. In particular, Aristotle wrote that the Sun, planets, and stars circled the Earth in a complex system of perfect circles. He thought that it had to be this way because of the beauty he saw in the sky, and he believed that circles were the epitome of perfection.
These ancient peoples even intuited concepts that were long dismissed until the advent of modern physics. Democritus, a Greek philosopher, posited the idea that all matter was made up of tiny atoms as well as void. He also thought that the Milky Way was made up of stars, and that other worlds like the Earth, some possibly inhabited, existed elsewhere among the stars.
In India, works on natural philosophy flourished as early as 3 millennia ago. There was an atomic theory of matter that is eerily similar to modern particle theory that was developed entirely through intuition and thought. Later, Buddhist philosophers posited that light was made of particles. This mirrors our modern concept of photons. In China, long dynasties proved fertile for the pursuit of philosophy, even Newton was preempted with the Chinese philosopher Mo Tzu intuited the first law of motion.
