Thursday, March 26, 2009

Arguments XXIV -- Strengths and Weaknesses Venue

I previously posted what I thought about the whole 'Strengths and Weaknesses' argument last year. Basically I disagree that a scientific theory has weaknesses! I know some folks want to disagree, but let me re-cap and you will at least see where I am coming from. Basically I said that a theory is based on what we know, how we know it, and why we know it. It gets tested, evaluated, measured against the existing evidence until it reaches the pinnacle of science, that of a Theory. Weaknesses in the theory would have been uncovered LONG before reaching that level! That's part and parcel of scientific methodology. Now that is not to say a Theory is perfect, or even complete. There are things that we do not know yet, but are they weaknesses?

Take a Bridge. You are building a bridge across a canyon, you aren't done yet, so does the bridge have a weakness because you haven't finished it? No! A weakness in the bridge would be something that when tested fails the test! A poor concrete poor, rust on a load-bearing truss . . .. That simple fact you haven't reached the end point isn't a weakness, but an indicator of future work to be done.

OK, that's my point about weaknesses in a nutshell, but what I really wanted to address was the most appropriate venue for dealing with the things we don't know. The real question here is the High School Science Classroom the appropriate venue for dealing with those issues? Now keep in mind the usual route to the HS biology class. Students get introduced to basic science methodology and many theories up to the point of studying biology and evolution in the 9th or 10th grade, which seems to be the norm around the country. So here you are, in the 9th or 10th grade, and you are getting into more detail about a specific theory, like evolution. Is this the right place to bring up the list of known unknowns? (The things we know we don't know, as opposed to the things we don't know we don't know.) There is the rub!

I do not believe it is. I think upper-level undergrad and graduate levels need to examine these areas, but the focus of HS science should be on the theories and the things that we do understand, and why we understand them, even how we reached this point of understanding. At best you might list some of the things we don't know yet, recognizing that it would be an incomplete list. But they are not weaknesses!

If you ant, go on Evolution Debate forum on Topix and see what some people think are weaknesses in the Theory of Evolution. Here are a few of the more common ones:

  • Evolution doesn't explain how life started on Earth -- True, but is this something we don't know about Evolution, or Chemistry? Abiogenesis is a separate area of study that is related to evolution, but evolution does not require to know it to understand how life has changed.
  • Evolution violates the Second Law of Thermodynamics -- Not true, for a number of reasons. The most basic is the Second Law applies to closed systems, and the Earth is definitely not a closed system.
  • The odds of Evolution being true are too high -- Are they? Who has calculated these odds with any degree of fidelity? No one, you have to understand the parameters involved to calculate the odds.
  • Randomness cannot explain complexity -- First of all, no one is saying Evolution is a random event. There is a random component (Random Mutation), but there are also components that select the results (Natural Selecting, Sexual Selection . . .) that are not random at all. So no one in Evolution is claiming that Randomness explains all.
OK, here is the rest of my point. Not one of the so-called weaknesses is an actual weakness in the theory of evolution, not one! The first is something we don't know in a related field, but the rest are misconceptions about evolution that anyone who actually understands the theory would know to be false.

This is what I am talking about, introducing a school standard that specifies 'weaknesses' must be covered and you are requiring a teacher to find weaknesses where there are none! What are they to do? Lists these as actual weaknesses when they are not? Create up a few more that make as much sense? Or start a conversation about the things we don't know?

So before we get students to the point of understanding the theory, we are going to start discussing the points of it that we don't know? Seems to violate the basic rules of teaching any subject. Get them well versed in the Theory and the Methodology and at that point they are in a position to understand the things we don't know. That can't happen in a high school science class! It's too soon and to easy to misinterpret as weaknesses.

Which is exactly the reason groups like the Discovery Institute are pushing so hard. They know there are no actual weaknesses in the theory, but if they build enough doubt in someone early enough in their understanding, then it will take much more work changing that preconception. This is nothing more than another gutter-style tactic i have come to expect from those folks over at the DI. They have failed to show how their own pet idea, Intelligent Design, is science, so they are trying to tear down science education!

Don't let them! Science is too important to our future to let it be damaged! The 'Strengths and Weaknesses' argument is a sham, a despicable tactic, and something we should toss out with the trash.


  1. Well, the "strengths and weaknesses" clauses are kind of weird.

    Strengths and weaknesses of scientific theories seem to me to be perfectly fair game in a HS science class. Especially tell students how scientists know what they know. That is, emphasize the experiments and the evidence. Emphasize the corollaries to the theory that prompted new experiments that also happened to work out.

    Teach weaknesses to some extent too...but really, what constitutes a weakness of a scientific theory depends on what you want it to do. No student should come out of a basic math class thinking that the + operation is supposed to be used to combine any two numerical values for any purpose whatsoever. No, the length of the hypotenuse is not a+b! On the other hand, quantum field theory (which HS students really shouldn't be forced to learn) doesn't behave well when in strong gravity. I suppose its entirely fair to tell students that evolutionary theory has as a weakness that a lot of the particulars of modern biology depends on details of populations and their environments that are pretty much lost to time.

    Those seem like completely legitimate and important things to be teaching in HS science classes. But why single out bio and evolution in particular? Why not emphasize the strengths and weaknesses of Newtonian mechanics? Because, of course, the people who try to insert that kind of language are trying to wedge in some completely made up "flaws"* in evolutionary theory, because they think evolution is stealing the thunder from their religion, or something. I don't entirely understand it, really.

    *there you go, a theory does have weaknesses, but a those weaknesses probably wouldn't usually be considered flaws

  2. I think we are pretty much in violent agreement. What you are calling a weakness is something I have no problem parameterizing, for example the theory operates well under these conditions . .like Newtonian mechanics. We certainly agree that they are not 'flaws'. We are just using slightly different semantics to express the same idea.

    I like your first paragraph very much. You could use Newton-Einstein-current gravitational theory in the same way. Show how Issac developed his theories, show how as we learned more we found areas where his work didn't fit the bill. We can show Einstein's theories help in those areas, and we can even show there are things happening that Einstein's theories don't fully explain. Did you know we have two vehicles leaving the Solar System traveling much faster than Einstein's work predicted, and we don't know why -- yet!

    It's not a weakness to discover something new and realize that the current theories don't fully explain it. That's scientific methodology in action, not a flaw in a theory.

    Thanks for your thoughts.