Map of life expectancy at birth from Global Education Project.

Monday, January 17, 2011

We are all superhuman now

I've finished reading Galileo's Dialogue, but it will be a while before I've said all I have to say about it. First this.

While much of the Dialogue concerns philosophy -- both epistemology and metaphysics, the latter necessarily with some circumspection -- Galileo of course had the ultimate weapon, his telescope. It was no longer viable to argue from some presumed first principles to discover the place of the earth in the cosmos. Anyone who looked through the telescope would be forced to concede the truth.

For some reason it's widely known that Galileo observed the phases of Venus and the moons of Jupiter. But the killer observation came because he could resolve the disks of Mars and Jupiter. They appeared many times larger when opposite the sun, and hence close to the earth, than when they were near the sun, and so much farther away. That is all you need to know beyond doubt that the earth cannot be at the center of the solar system.

The church authorities, famously, refused to look through the telescope. Galileo's most important contribution to the scientific revolution was not so much his radical epistemology and his scientific imagination. These were not unique to him, although he was certainly among the pioneers. It was his application of a newly invented instrument to observation of the natural world.

Like Copernicus, who intuited the cosmos, Darwin needed only his senses and his reason to derive evolution. But we could not really understand evolution, and sweep away all objections, until biochemistry and X-ray crystallography enabled people to elucidate the mechanism of inheritance and demonstrate descent and relatedness among species directly. Although biologists still go out and just look at stuff, most scientific research nowadays depends on tools that enormously extend and magnify human senses, and now, with computers, the human intellect.

There is a massive structure of machinery and inference through which knowledge flows to us. And I admit, you have to trust it. Back in Galileo's time, people objected that the telescope was somehow distorting reality. Nobody doubts telescopes any more, but there are still plenty of people who doubt scientific conclusions. And being convinced is no longer quite as simple as looking through the telescope. Scientists don't even really understand each other's work, after all. They have to trust each other. But they do because it pays off. Applying physics and chemistry to biology and astronomy pays off. It all fits together. It works.


C. Corax said...

I'm struggling through "How to Teach Physics to Your Dog" by Chad Orzel. That would be quantum physics. The concepts sound completely off the wall to me, like some weird made-up religion; but scientists know how to test the theory (for the most part) and it works. It has real-world applications.

It blows my mind that people were able to think up the theories and to know that they were right, even when they couldn't explain WHY they were right.

Cervantes said...

Quantum theory is particularly esoteric because it describes phenomena which are not part of the world or our senses at all. We can see the planets and the stars, and a telescope just makes our vision more powerful. But the quantum world just doesn't behave like the macro world in which we live. It's how physicists today understand something about the deep structure of reality -- a mathematical description that successfully predicts the outcomes of experiments. It can't really be encompassed by human intuition.

roger said...

"I think I can safely say that nobody understands quantum mechanics."

* Richard Feynman, in The Character of Physical Law (1965)

he should know.