Saturday, August 20, 2011

The Motion Mystery

Even to eminent thinkers, an explanation for motion was seemingly unknowable near the turn of the 20th century.

For example, in the late 19th century Thomas Huxley said that "existence, motion, and law-abiding operation in nature are more stupendous miracles than any recounted by the mythologies...".

Santiago Ramón y Cajal went further in the early 20th century, writing, "there is no doubt that the human mind is fundamentally incapable of solving these formidable problems (the origin of life, nature of matter, origin of movement, and appearance of consciousness)."

It turns out that in the early 21st century we now have a pretty good answer to this mystery. That answer comes in the form of molecular machines.

As Steven Pinker explains, "the stuff of life turned out to be not a quivering, glowing, wondrous gel but a contraption of tiny jigs, springs, hinges, rods, sheets, magnets, zippers, and trapdoors...".

One example of such a machine is ATP synthase, which literally works like a rotor:

Now, molecular machines don't explain why atoms themselves move (you'd need to go deeper for that), but their existence certainly does explain why you can move in the absence of an outside force and a rock cannot.

If we don't kill ourselves (from, e.g., an environmental disaster or nuclear war) first, we will to continue to solve puzzles that some of us currently consider intractable mysteries.

And in the meantime, we should cultivate some doubt in our doubt of the potential of science.