December 21, 2005

What is science?

In yesterday's Dover opinion, Judge John E. Jones has written a lucid definition of science that deserves to be in textbooks (p. 64):

Expert testimony reveals that since the scientific revolution of the 16th and 17th centuries, science has been limited to the search for natural causes to explain natural phenomena. This revolution entailed the rejection of the appeal to authority, and by extension, revelation, in favor of empirical evidence. Since that time period, science has been a discipline in which testability, rather than any ecclesiastical authority or philosophical coherence, has been the measure of a scientific idea’s worth.

In deliberately omitting theological or “ultimate” explanations for the existence or characteristics of the natural world, science does not consider issues of “meaning” and “purpose” in the world. While supernatural explanations may be important and have merit, they are not part of science. This self-imposed convention of science, which limits inquiry to testable, natural explanations about the natural world, is referred to by philosophers as “methodological naturalism” and is sometimes known as the scientific method.

Methodological naturalism is a “ground rule” of science today which requires scientists to seek explanations in the world around us based upon what we can observe, test, replicate, and verify.

Update 12/31: Here for more thoughts from John Polkinghorne and others

Posted by David at December 21, 2005 11:32 AM

How well does evolution between species fit into this definition of science? Can this kind of macro evolution be tested? Replicated? Is evolution truely a scientific endeavor, or is more of a science-inspired metaphysical idea?

Posted by: Chouser at December 21, 2005 02:07 PM

The decision says teachers can't even mention the fact that an alternative theory to Darwinian evolution exists.

In the 16th centry, scientists were jailed for creating theories that excluded a god. In the 21st century we have the converse: teachers may be jailed for mentioning the existence of a theory that may include a god.

Aren't these policies equally wrong?

Posted by: Peter H. at December 21, 2005 06:39 PM

Interesting comments.

Of course, scientists wouldn't study macro evolution unless it could be tested; and they test it every day.

Theories that imagine a timeline that looks back in time can have predictive value for things that we can see today. For example, various big bang theories can predict the characteristic shape, frequency, and distribution of the cosmic microwave background. The closer we look at the sky, the more carefully we can pick between competing theories.

Theories on the macro evolution of species predict characteristic patterns of genetic drift in nuclear and mitochondrial DNA; the closer we look at various species' DNA, the more carefully we can pick between competing evolutionary theories.

Theories that have no predicitive power are not part of science - after all, what would the experimentalists do with all their time?

Teachers thrown in jail? Not happening. Scientists are framing the discussion more crisply than that. They do not speak of "morality of science." For them, the question is not about morals; it's about "what science is and what it is not."

The text book message: matters of "faith," "meaning" and "purpose" are not part of science.

Maybe matters of "theory," "prediction" and "verification" should be excluded from religion.

Posted by: David at December 23, 2005 06:28 AM

David, thanks for avoiding ad hominem comments that so often are a part of discussions on this topic. Not that I would have expected any less from you.

It is interesting to me that the definition quoted says "observe, test, replicate, AND verify" [emphasis mine]. You have addressed testing of macro evolution, and I'm willing to grant you that. In fact, if that testing has been verified, that requirement has also be fulfilled. But what of the other two requirements?

I don't think that observing your own test counts for the observation requirement -- generally you want to have observed the behavior "in the wild", wouldn't you?

Even if observation of DNA fulfills the observation requirement for macro evolution, what about replication? Has any experiment been created to reproduce macro evolution?

None of my objections amount to anything close to proof that macro evolution hasn't taken place, but has intelligent design been disproved either?

Testing the theory that a being that created the universe, has similar (if not worse) problems for replication. But creation would have been observed, if only by the creator. I can understand an unwillingness to accept scripture as scientific documentation of an observation, but I think it's interesting to mention.

But if testing DNA to verify the theory of macro evolution is acceptable, is similar secondary testing of creation ok as well? We might expect to find evidence of the creator in things like creative beauty throughout the universe, a sense of spirituality that crosses cultural boundaries, and a more or less consistent sense of a morality that values the life that the creator made.

Of course many scientists and others will simply dismiss such "evidence", and I don't really expect to persuade anyone with a few poorly arranged words like this. But I think that when it comes to convincing someone of a truth, prejudice, upbringing, and the consequences of accepting that truth generally trump evidence anyway, regardless how prevalent that evidence is.

Posted by: Chouser at December 24, 2005 02:10 AM

Is the power meter on the side of your house a direct way to observe electricity? Is there any way to directly observe electrons?

Most science relies on indirect observation. Yet I think epidemiologists who are furiously trying to track the evolution of the avian flu (or drug-resistant bacteria, or evolution of herbicide-resistant weeds) would tell you that natural selection is on pretty solid ground. They use the theory to predict events that they wrestle with every day, and it works well enough that they don't worry about it any more than you worry about your power meter.

On the other hand, science teaches us to be always skeptical of a theory. A theory gets thrown out by science when it fails to work. If the theory is not useful, it gets rejected.

Really, this is the the thing that bothers me about the whole Creation Science movement. By putting scripture into the crosshairs of science, by measuring religion using methodology of science, it does damage to the understanding of religion.

The essence of religion is the leap of faith. It is in believing in something that is outside ourselves and outside all evidence. Religion is about embraing a larger purpose that is beyond all our inward-looking self-obsessed, self-interested instincts.

If we apply the scientific method to scripture, it means rejecting the parts that don't stand up to verifiable observations. Is this a way of being more faithful, or is this a way to reject faith? If we only accept the parts of religion that we can test, does that make the universe more meaningful, or does it make religion vacuous?

Applying the scientific method to religion seems like a terrible mistake to me.

Posted by: David at December 26, 2005 07:37 AM

(I initially tried sending this to 'Chouser' but my email was returned, so here's my post)

I've been reading with interest your well written comments on David's blog about I.D. I'm a christian and accept by faith that God created the world but I'm interested in encouraging mutual respectful dialog between people who believe in macro-evolution. I said believe because my personal un-tested thesis is that those who proscribe to macro-evolution do so more through faith than by actual reliance on a large body of evidence.
I've just started searching internet sources in order to find the basis of evolutionist's acceptance without question of macro-evolution. I have not found much yet but I intend to keep trying. Perhaps you know what their points of evidence are.
I suppose I'm bothered by my perception of the media's slant towards portraying those trying to get I.D. mentioned in schools as members of a right-wing plot trying to establish a religion or a theocracy (perhaps a small percentage are). It concerns me because these knee-jerk reactions of those in the media and many scientists serve only as a hindrance to mutual understanding. I'm willing to look squarely at my biases but are they? I think it would help me if I really understand what evidence for macro-evolution does exist. I'd appreciate your thoughts on this.
Kind regards,

Posted by: Paul Dyches at December 28, 2005 01:46 PM

The most convincing work in human origins (in my opinion) is the phylogeny work based on analyzing variations in DNA in modern populations. Geneticists have taken a variety of approaches, such as comparing differences in synonymous and non-synonymous mutations, mitochondrial DNA, nonrecombining Y chromosome DNA, and lots of other clever techniques (like tracking patterns of retorviral insertions).

Some examples:

Lots of other references on how phylogenies are deduced can be found on the website, for example:

Some textbook content on the subject:

I also find the recent work in using population genetics to infer human prehistory very interesting. For example:

Posted by: David at December 29, 2005 02:18 AM

does the all laws of darvinism is applicaple to plants also.

Posted by: at October 1, 2006 10:41 AM
Post a comment

Remember personal info?