Science of Discworld III

attitude. Once God is removed from the day-to-day running of the planet, and installed somewhere behind DNA biochemistry and the Second Law of Thermodynamics, it is no longer so obvious that He must be fundamental to people’s daily lives. In particular, there is no special reason to believe that He affects those lives in any way, or would wish to, so the fundamentalist preachers could well be out of a job. Which is how Darwin’s lack of a Nobel can become a debating point on American local radio. It is also the general line along which Darwin’s own thinking evolved – he began his adult life as a theology student and ended it as a somewhat tormented agnostic.
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    Seen from outside, and even more so from within, the process of scientific research is disorderly and confusing. It is tempting to deduce that scientists themselves are disorderly and confused. In a way, they are – that’s what research involves. If you knew what you. were doing it wouldn’t be research. But that’s just an apology, and there are better reasons for expecting, indeed, for valuing, that kind of confusion. The best reason is that it’s an extremely effective way of understanding the world, and having a fair degree of confidence in that understanding.
    In her book Defending Science – Reason the philosopher Susan Haack illuminates the messiness of science with a simple metaphor, the crossword puzzle. Enthusiasts know that solving a crossword puzzle is a messy business. You don’t solve the clues in numerical order and write them in their proper place, converging in an orderly manner to a correct solution, unless, perhaps, it’s a quick crossword and you’re an expert. Instead, you attack the clues rather randomly, guided only by a vague feeling of which ones look easiest to solve (some people find anagrams easy, others hate them). You cross-check proposed answers against others, to make sure everything fits. You detect mistakes, rub them out, write in corrections.
    It may not sound like a rational process, but the end result is entirely rational, and the checks and balances – do the answers fit the clues, do the letters all fit together? – are stringent. A few mistakes may still survive, where alternative words fit both the clue and the words that intersect them, but such errors are rare (and arguably aren’t really errors, just ambiguity on the part of the compiler).
    The process of scientific research, says Haack, is rather like solving a crossword puzzle. Solutions to nature’s riddles arrive erratically and piecemeal. When they are cross-checked against other solutions to other riddles, sometimes the answers don’t fit, and then something has to be changed. Theories that were once thought to be correct turn out to be nonsense and are thrown out. A few years ago, the best explanation of the origin of stars had one small flaw: it impliedthat the stars were older than the universe that contained them. At any given time, some of science’s answers appear to be very solid, some less so, some are dubious … and some are missing entirely.
    Again, it doesn’t sound like a rational process, but it leads to a rational result . Indeed, all that cross-checking, backtracking, and revision increases our confidence in the result. Remembering, always, that nothing is proved to the hilt, nothing is final .
    Critics often use this confused and confusing process of discovery as a reason to discredit science. Those stupid scientists can’t even agree among themselves, they keep changing their minds, everything they say is provisional – why should anyone else believe such a muddle? They thereby misrepresent one of science’s greatest strengths by portraying it as a weakness. A rational thinker must always be prepared to change his or her mind if the evidence requires it. In science, there is no place for dogma. Of course, many individual scientists fall short of this ideal; they are only human. Entire schools of scientific thought can get trapped in an intellectual blind alley and go into denial. On the whole, though, the errors are eventually exposed – by other scientists.
    Science is not the only area of human thought to develop in this flexible way. The humanities do similar things, in their own manner. But science imposes this kind of discipline upon itself more strongly, more systematically, and more effectively, than virtually any other style of thinking. And it uses experiments as a reality check.
    Religions, cults, and