One of a series of quick posts on the six sections of my book The Big Picture — Cosmos, Understanding, Essence, Complexity, Thinking, Caring.
Chapters in Part One, Cosmos:
1. The Fundamental Nature of Reality
2. Poetic Naturalism
3. The World Moves By Itself
4. What Determines What Will Happen Next?
5. Reasons Why
6. Our Universe
7. Time’s Arrow
8. Memories and Causes
It wasn’t easy to settle on how to organize all the material in The Big Picture. Ultimately I decided to start with the universe — a bit of cosmology, yes, but also some basic features of how the universe physically operates. Features that played a crucial role in the transition from an ancient view of the world, which still lingers on in our informal “manifest image” of how things work, to our modern scientific view.
One important step in that transition was the seemingly-innocuous realization that momentum is conserved. In Aristotle’s physics, to keep something moving you had to keep pushing it. That’s a very sensible thing to believe, since it’s absolutely true in our everyday experience. It took many centuries of thinking by very smart people (including Persian polymath Ibn Sina, right) to realize that ...