The News Is Not The News
On the ice-capped heights of Labrador, through winter, snow falls. With the coming of spring, much of it melts. Sometimes more falls than melts, and the ice grows; sometimes more melts than has fallen, and the ice shrinks. It is a delicate balance. The result varies from year to year, by many inches. But let the balance tip ever so slightly, so that amidst much larger fluctuations one inch on average survives, and Earth is transformed. Great glaciers grow, and cover North America in ice.
If corresponding processes in Greenland or Antarctica tip the other way, melting more than is frozen, then oceans will swell, and drown North America's coasts.
Episodes of both sorts have happened repeatedly in Earth's history, on timescales of a few tens of thousands of years. They are probably controlled by small, long-period changes in Earth's orbit. Today we are living in a relatively rare interglacial period, expected to last another fifty thousand years. Notoriously, over the last few decades human activity has tipped the balance toward melting, threatening catastrophe.
These mighty stories derive from systematic trends that can be hard to discern within the tumult of much larger, but ephemeral, noise. The news is not the news.
So it is with the grandest of human stories: the steady increase, powered by science, of our ability to control the physical world. Richard Feynman memorably expressed a related thought
From a long view of the history of mankind, seen from, say, ten thousand years from now, there can be little doubt that the most significant event of the 19th century will be judged as Maxwell's discovery of the laws of electrodynamics.
In that spirit, the most significant event of the 20th century is the discovery of the laws of matter in general. That discovery has three components: the frameworks of relativity and quantum mechanics, and the specific forces laws embodied in our core theory, often called the standard model. For purposes of chemistry and engineering—plausibly, for all practical purposes—we've learned what Nature has on offer.
I venture to guess that the most significant event of the 21st century will be a steady accumulation of new discoveries, based on deeper use of quantum physics, which harness the physical world. In the 21st century we will learn how to harvest energy from the Sun, and to store it efficiently. We will learn how to make much stronger, much lighter materials. We will learn how to make more powerful and more versatile illuminators, sensors, communication devices, and computers.
We know the rules. Aided by our own creations, in a virtuous cycle, we'll learn how to play the game.
