… Any one of a million things could fail and cause our complex civilization to collapse for an hour, for a day, or however long. That's when you find… - James Burke

An invention acts rather like a trigger, because, once it's there, it changes the way things are, and that change stimulates the production of another invention, which in turn, causes change, and so on. Why those inventions happened, between 6,000 years ago and now, where they happened and when they happened, is a fascinating blend of accident, genius, craftsmanship, geography, religion, war, money, ambition... Above all, at some point, everybody is involved in the business of change, not just the so-called "great men." Given what they knew at the time, and a moderate amount of what's up here [pointing to head], I hope to show you that you or I could have done just what they did, or come close to it, because at no time did an invention come out of thin air into somebody's head, [snaps fingers] like that. You just had to put a number of bits and pieces, that were already there, together in the right way.

You can only know where you're going if you know where you've been.

Take movement for example. Forces acting up, down, or from side to side. You make theories to explain it all, but you might well remember that it was you that invented them all. For Mach there was no reason to believe the rest of the cosmos was doing what your little bit was doing, so science should only describe not try to explain. Even description is relative. Am I moving or is the back ground? Or take the position of a star. It depends on the position you see it from, which depends on the date and time, which in turn depends on the position of the earth, in a solar orbit, in a solar system, moving around the edge of a Galaxy which may be moving away from other Galaxies. Say that you've decided that I'm moving and the background is standing still. Is the background moving relative to something else?