Miscellaneous · Science

Knowing Like A Crossword Puzzle

If you enjoy solving crossword puzzles, you may have found yourself in the same position as I did the other day:
Crossword puzzle

“Thug” is “GOON”, obviously: the O’s fit “OIL” and “NOTONYOURLIFE”. As for the G, well, I know nothing about ballet, so for all I know there’s someone named Twyla T. Garp out there.

I didn’t know what “With feet all askew” could be, but worked on filling in the words that intersected it, until eventually it became obvious that “_IGEONTOEN” couldn’t be right. The problem lay either in “GOON” or in “_IGEONTOEN”, but both were connected to other words: fixing one might unravel a whole section of a puzzle that seemed to fit together quite well. I wasn’t sure about “Zubin of music” → “MEHTA”, but other than that, my answers seemed pretty solid.

Eventually, of course, I figured out that “With feet all askew” was “PIGEONTOED”, and “Thug” was “HOOD” (though the name Twyla Tharp still doesn’t ring any bells).

And this strikes me as a good metaphor for how we understand the world.

We don’t know anything with absolute certainty: I don’t know for sure that George W. Bush is president of the United States, or that there’s such a place as Australia, or that the atomic number of uranium is 92. Any individual fact that you or I believe could potentially be wrong.

But each fact is interconnected with other facts. Independent sources from around the world say that uranium is element #92. Several countries have built nuclear power plants and nuclear weapons, including Israel and the Soviet Union. I played with a sample of uranium for a High School science project, and it behaved just as my science teacher said it ought to, the same science teacher who said that uranium had atomic number 92. All of these facts are connected to — and reinforce — each other. It’s like a corner of a crossword puzzle where a lot of words intersect each other.

Any given “fact” could be wrong, but some sets of might-be-wrong facts fit together better than others, and when lots of facts intersect and confirm each other, it increases the likelihood that all of them are correct.

Of course, it’s sometimes necessary to reconsider a whole bundle of interconnected facts, just as it is sometimes necessary to redo a whole corner of a crossword puzzle. For centuries, it was natural to think that the Earth was stationary, and at the center of the universe: the ground doesn’t feel as though it’s moving. The sun and moon look about the same size as a large building a few miles away, the stars wheel overhead like diamonds attached to a sphere, and so forth.

But over time, the well-confirmed fact that the Earth is immobile and at the center of everything kept running into other facts that didn’t quite fit, like my “Twyla T. Garp”, above: the increasing number of epicycles required to explain the motion of the planets, moons revolving around Jupiter, the fact that lunar eclipses only happen during a full moon, and so forth. Eventually, it had to be conceded that a new answer, that the earth is just another planet, and that they all revolve around the sun, fit the observations better.

Dismissing Woo out of Hand

This is also why I don’t bother checking whether any given “psychic” might really have magic powers, or whether the next astrologer along might be the real McCoy, or whether the moon landings were a secret hoax by NASA: facts like “Neil Armstrong really did walk on the moon”, while certainly not 100% proven, are in the middle of a huge tangle of interrelated and mutually-confirming facts (including photos, video footage, Phil Plait’s debunkings, the idea that ten thousand NASA employees and contractors can’t possibly keep a secret for forty years, the fact that the Soviet Union was certainly tracking the Apollo rockets and would have loved to publish telescope photos of the alleged landing site and show the world that the capitalist imperialists were lying, etc.). If someone says that the moon landings were faked, it could be that:

  1. That person is mistaken.
  2. That person is lying.
  3. An immense bundle of interrelated facts have to be unraveled and put back together in light of the NASA hoax.

I hope you’ll agree that either #1 or #2 fits the tangle of facts much better than #3.

Taking Potshots at Theology

A while back, Alvin Plantinga wrote a particularly clueless article. One of the worst bits was this:

Like most naturalists, Dawkins is a materialist about human beings: human persons are material objects; they are not immaterial selves or souls or substances joined to a body, and they don’t contain any immaterial substance as a part. From this point of view, our beliefs would be dependent on neurophysiology, and (no doubt) a belief would just be a neurological structure of some complex kind. Now the neurophysiology on which our beliefs depend will doubtless be adaptive; but why think for a moment that the beliefs dependent on or caused by that neurophysiology will be mostly true? Why think our cognitive faculties are reliable?

(emphasis added)

In other words: evolution is about what works well enough today, and not about producing an optimal design, or about producing a true image of the world. For instance, electromagnetic radiation comes in many frequencies, but we only see three primary colors (and combinations thereof) because that was easier to evolve, and it works well enough. Plantinga’s question is just a generalization of the eye example: could it be that the world we perceive is completely different from the real world? Perhaps when a tiger jumps out at me, I perceive it as a glass of water on my table, and when I think I’m lifting the glass to my lips, I’m really sending my legs the order to run away. What sounds like traffic outside the window is really the grass on my feet, and the breeze is really branches brushing my face.

By now you should see where I’m going with this: Plantinga’s question is akin to imagining that I have a crossword puzzle with most of entries filled in, all criss-crossing each other, and all of the words fit the clues — and yet, my solution is completely different from the official one at the back of the magazine. It’s possible, of course. But it’s astronomically unlikely. Plantinga agrees that natural selection seeks that which is adaptive, not that which is true. But it seems obvious that of all of the cognitive frameworks that are adaptive (i.e., which work well enough most of the time), the ones most easily reachable by natural selection will be the ones that lie fairly close to the truth.

The Coming Scientific Revolution

Today, physics is like a crossword puzzle with two sides almost completely filled in, but where they meet, the answers don’t quite fit: general relativity is very very good at explaining really massive objects, and quantum physics is very very good at explaining really tiny objects. But it’s known that if you look at something that’s really massive and really tiny (like, say, the Big Bang), the two give somewhat different results. Eventually, someone will figure out how to make them fit (hopefully without unraveling one or both sides), and that someone will win a Nobel Prize.