30 September 2005

Science Words


Eleven parents of students at a Pennsylvania high school are suing over the school district's decision to include "intelligent design" -- an alternative to evolution that involves a God-like creator -- in the curriculum of ninth-grade biology classes.

The parents and the American Civil Liberties Union (ACLU) say the policy of the Dover Area School District in south-central Pennsylvania violates the constitutional separation of church and state, which forbids teaching religion in public schools.

The school board says there are "gaps" in evolution, which it emphasizes is a theory rather than established fact, and that students have a right to consider other views on the origins of life.

(CNN)


The problem in this story, and much of the "evolution is only a theory" story, is that English and Science are different languages that share a few words, but they mean different things. I figured I'd give a few definitions / explanations here of some words commonly used in the evolution versus ID argument.

Fact/Know/True
English: Something that is absolutely correct, beyond the shadow of a doubt.
Science: These terms are not generally used as their meanings are imprecise. Sometimes when talking w/ laypeople they're used to mean "observation," other times to mean "theory." When talking to other scientists we use different words. Nothing in science can be "known" absolutely as "true," so these words are meaningless.

Observation/Measurement
English: (self-evident)
Science: Data, numbers. This is the only stuff we "know" for "sure" is "true," and even then there can be mistakes in the scientist's methods to get the data. ("Data" is plural, "datum" is singular.) "Observation" is sometimes used to refer to the first step of the Scientific Method, which is also called "Question" at times.

Hypothesis
Science: An untested educated guess about the REASONS or explanation behind what's being experimented upon. May be proven correct or incorrect in the long run. Leads to predictions for specific experiments, and if consistently upheld leads to a theory.

Prediction
Science: A guess about the results of a particular experiment before we've done anything on it. Meaningless in the long term, because (1) it only applies to that specific experiment, and (2) it gets supplanted by data and theories.

Law
Science: A theory that can be expressed in simple terms, such as an easily memorized sentence, or a formula. I've seen many other definitions for the term Law, but this is the one I like. Some such "laws" have since been disproven, or were based upon faulty assumptions, but by tradition they are still called laws.

Theory
English: An untested guess at a reason, with a high chance of being wrong.
Science: A hypothesis that's been tested many many times for many years and hasn't ever been disproven. It's impossible to ever prove anything is absolutely "true" in science, as there is always the possibility of other explanations. A theory is the most likely one, and is as close to being "true" or "right" as scientists will ever admit. (Think of scientists as a non-committal boyfriend who won't say "I do." When he says "if I were going to marry anyone, it'd be you," that's like scientists saying "this is our theory, it hasn't been disproven yet.") Theories are often refined as time progresses, but rarely proven entirely wrong.

For example the geocentric solar system / universe proved wrong and was changed to the heliocentric model. It was refined when we determined the distance to stars, so we knew that the solar system was just part of the universe. Hubble further discovered (1923) that there were other galaxies than our own. Similarly, the reasons behind it all were refined, as Aristotle's "natural motion" turned into Galileo's inertia, Newton's gravity, and then Einstein's General Relativity (~1910). Further tweaks are continuing as Stephen Hawking and others study information in black holes and string theory.

Evolution is a good example of a theory still in the process of being refined at a coarser level. Where we are with evolution would be somewhere between Newton and Einstein with gravity, or between knowing the distance to stars and the distance to galaxies. Natural selection was presented before Darwin (I believe). Darwin extrapolated that, carried to extremes, natural selection could mutate species into other species, and that process was called evolution. During the 20th century it was recognized that there were distinct times when new species "quickly" (hundreds of thousands of years) developed, and this has been incorporated into an updated version of evolution called punctuated equilibrium (not often taught in K-12 schools, sadly). This refinement of the theory of evolution states that environemtnal triggers, such as massive habitat change brought on by a comet or asteroid collision, or ice ages or global warming, would cause "rapid" evolution of new species - faster than can be captured in the fossil record, but still gradual in terms of tens of thousands of generations.

Current-day theory about the geography of the universe is pretty solid. Current theory on gravity/GR (General Relativity) has a major gap, in that we can't yet reconcile GR with quantum mechanics. But we're working on it. Current theory on evolution is pretty solid but has some small gaps, in that we haven't found missing links from the evolutionary explosions, and some subsystems seem difficult to evolve in small steps. But we're working on it.

3 comments:

doris said...

I'd love to have you as my physics teacher! You have an interesting way of putting things across.

It is quite funny reading through your definitions - which I understand and agree with - because of the "non-committal boyfriend law" which I think is also correct. Things can't be said to be a fact because nothing seems to be absolute. The funny bit is that on reading these definitions it sounds like scientists make mistakes; are never absolutely sure; and involved in meaningless predictions and can't add up right!

I'm one of those "evolution [big bang etc] is only a theory" people but just because I think that doesn't mean that religious faith is going to fill the void.

Is the teaching of religion really forbidden in US schools or is it the practise of religion? In UK schools we have religious studies which I think is very important although probably quite superficial. But if only a taster of the different religions out there it at least broadens our horizons.

But most of all we need better science teachers and more provision for science so that it is as interesting and an essential part of life as the gossip columns. If more lay people were able to access it then we might likely end up being better educated in these subjects.

Thank you for posting on this subject of semantics. I fear I may have gone slightly off-topic on it.

zandperl said...

Doris,

Scientists definitely make mistakes! Einstein himself (1) mistakenly said that he didn't think the universe could be expanding, so he (2) fudged his math to make it work out that the universe was the same size forever. He named that fudge factor the "cosmological constant," and later said it was his biggest mistake. Come to find out in the 1990's and 2000's that (3) the universe is not only expanding, it's acceleratingly so, and that cosmological constant is now what we know as Dark Energy.

To sum, there were at least three mistakes in that story, and there may still be more! One of the cornerstones of science is that we're never sure of anything, and therefore science is always evolving. (Einstein also didn't believe in quantum mechanics.)

As for religion in US schools, state-sponsored schools are not allowed to teach religion as a fact (private schools can do whatever they want). They are allowed to teach aspects of religions as literature, history, or comparative cultures (hence I learned more about Hindu and Buddhism in school than I ever did Christianity). Whether schools (and other public institutions) are allowed to *celebrate* religious events is still contested ground. The reason I (and others) argue ID should not be taught in science is that it's not scientific (i.e., it's not testable). Whether it is religious is secondary.

Is it true that in Britain there IS a state religion, and that priests actually have a say in the government (House of Lords) just because they're priests? And I'm under the impression that in France you've got the opposite extreme, that they're not allowed to show religious garments or jewelry or anything in public institutions (the whole headscarf banning incident from last year).

Dread Pirate Robert said...

Thanks for your post - it sums up what a theory is quite nicely and forces proponents of ID to review their positions. Which they won't anyway, but at least we tried. Willful ignorance, I reckon.