I'm pleased by the almost universal condemnation of John Tory's remarks about creationism in schools [John Tory Promotes Creationism]. Letters to the newspapers are running overwhelmingly against the leader of the Ontario Progressive Conservatives. However, there's still lots of misunderstanding out there even though their hearts are in the right place.
In today's Toronto Star there's a letter from a reader in Barrie, Ont. The title is Misunderstanding of the word `theory'. I'll quote most of the letter ...
John Tory's statement appearing to equate Darwin's theory of evolution with "other theories that people have out there" comes from a common misunderstanding the general public has about the scientific meaning of the word "theory."This is not right. Theories are explanations of natural phenomena and laws are simple descriptions of phenomena. Boyle's Law, for example, simply states that "For a fixed amount of gas kept at a fixed temperature, P and V are inversely proportional." It does not explain why this is so. That's what the theory of the behavior of gases would do.
When a scientist has an idea he or she wishes to test through observation or experimentation, this is termed a hypothesis.
Once a body of scientific data has been accumulated in support of the hypothesis, it is elevated to the status of theory.
After a time, certain theories receive considerable support from various scientists and no contradictory evidence turns up. Then, the theory may be elevated to the status of law.
There is now so much evidence from many branches of science supporting Darwin's theory of evolution by natural selection, that it may be time to give it the status of a law.
Evolutionary Theory is a complex subject that attempts to explain how species evolved. It incorporates Darwin's Theory of Natural Selection and other things like random genetic drift and mechanisms of speciation. Evolutionary Theory will never become a law. Theory is as good as it gets in science.
11 comments :
I dunno, Larry. Maybe we should make it a law, so we could fine and imprison people who oppose that law.
One thing that annoys me is that so many of those who rightly complain about the abuse of the word 'theory', especially by creationists, often use the term interchangeably with it's more common general meaning themselves, thus adding to the confusion.
Ian's right...recent case in point, Scientific American's "What is the latest theory of why humans lost their body hair?." They should know better (Dr. Moran: I almost blamed that post headline on you).
There have certainly been attempts at laws of evolution.
AJ Lotka, 1922: "..(I)n the struggle for existence, the advantage must go to those organisms whose energy-capturing devices are most efficient in directing available energy into channels favorable to the preservation of the species."
Vladimir Vernadsky, 1926: "(T)he evolution of species, in tending towards the creation of new forms of life, must always move in the direction of increasing biogenic migration of the atoms in the biosphere."
Is Fisher's fundamental theorem of natural selection a law? Does it matter?
Tupaia
It's the ladder theory of theory ... or something.
Law of evolution? Um, what about "biological systems shows common descent"?
Law of evolution? Um, what about "biological systems shows common descent"?
All of them? Some of them? The common descent of all biological systems is more an observation than a requirement.
How about:
...if variations useful to any organic being ever do occur, assuredly individuals thus characterised will have the best chance of being preserved in the struggle for life; and from the strong principle of inheritance, these will tend to produce offspring similarly characterised.
windy:
The common descent of all biological systems is more an observation than a requirement.
True. But that is not a problem, IMO.
Allow me to temporarily go to areas which are more familiar to me:
The entropy increase in the second law of thermodynamics is more an observation than a requirement. It can't be derived from theory AFAIU.
[Which is perhaps why Boltzmann committed suicide when people argued over his proof, which I believe is considered to fail in subtle ways connected to time symmetry.]
Similarly, computer scientist Scott Aaronson argues for the seemingly unprovable but universal observable "NP Hardness assumption", that we can't solve NP hard problems efficiently (formally, NP != P):
I see this principle as analogous to the Second Law of Thermodynamics or the impossibility of superluminal signalling [sic]. That is, it’s a technological limitation which is also a pretty fundamental fact about the laws of physics. Like those other principles, it could always be falsified by experiment, but after a while it seems manifestly more useful to assume it’s true and then see what the consequences are for other things. [My bold.]
Furthermore, this observation is connected to the existence of closed timelike loops (CTL) in physics. They would permit time travel and then P=NP, which means every problem would in principle have an easy solution. So equivalently you could argue that absence of CTL is an observation that should be promoted to law too.
Returning to biology, I thought common descent was a local property by theory, ie all life obey this whether lateral transfer et cetera is observed. (Btw, as I understand it, it is given by heredity which could be another formulation of a law.)
And that it is the global property that is observed, or not. I.e. it seems we can't really know if current life started uniquely or if different progenotic communities consolidated.
[Actually, it may be awkward to promote the global assumption. What if we observe life elsewhere?]
windy:
An afterthought. Your proposal is stronger, so if it can pass the approval of the "drifters" and other schools it is preferable. As I understand it, it says that variation is better than no variation in inheritance. And we do observe variation...
One might suppose that by upgrading the complexity level of the concepts employed one can reduce Darwin to ‘law’ form. Thus, for example:
Random walk diffusion in the complexity space of the cosmic physical regime is sufficient to ensure that in a realistically finite time relatively stable complex adaptive systems will evolve
That’s my first shot, perhaps an expert like yourself could do a lot better. Note my use of shifty-fuzzy concepts like ‘complexity space’, ‘ physical regime’ ‘realistically finite time’, ‘complex adaptive systems’.
My own view is that everything is a theory in a gradation of complexity. Theories like Boyle’s law deal with less complex objects like P, T, & V. But even that is relative. In absolute terms Boyle’s law is highly complex, requiring for example quite intricate judgments about the situations in which it should apply. However, it pales in comparison with ‘Darwin’s law’ or … wait for it ….the ‘theistic conjecture’.
Tegumai Bopsulai, FCD says,
I dunno, Larry. Maybe we should make it a law, so we could fine and imprison people who oppose that law.
Hmmm ... how do you break the law of evolution?
Note to Torbjorn: Very interested in your comment: I'm studying it!
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