Petr Kuzmic wrote:
>Jannie Hofmeyr wrote:
>>> So, in the sense of calculating control coefficients it is not
>> important to know which mechanism is followed, only what the value of
>> the elasticity is (and this can of course be obtained
>> experimentally).
>>Thanks for kindly educating me and possibly others reading this about
>the basic principles of MCA. I think I am starting to get it (even
>without venturing out to the library): MCA adopts a completely empirical
>as opposed to mechanistic approach to model building.
>>This brings to mind what Box et al. said...
>>Can this be a problem in trying to understand the behavior of
>biochemical systems over a sufficiently wide range of conditions?...
This is pertinent, but it's not the whole story. The point is that even if
you know a lot about the internal workings of a system it's still often
very helpful to step outside and treat it as a black box, and we do this
all the time in science and technology. We all know that Schroedinger's
wave equation underlies all chemistry, but if we tried to discuss the
properties of alkaloids in terms of wave mechanics we'd soon get lost in a
huge mass of details. Even people who understand in detail how a petrol
engine works still learn to drive at a black box level: if you turn this
wheel clockwise the car will move to the left, never mind the physics of
why.
According to Daniel Dunnett in his book "Darwin's Dangerous Idea" (1995 or
thereabouts) Crick was highly critical of this approach as applied to
understanding the brain and consciousness ("These people may be good
engineers, but what they're doing is terrible science, because they're
deliberately closing their minds to what we already know about brain
function...") and Dunnett asked him if he would make the same criticism of
population geneticists (who deliberately close their minds to what is known
about gene structure and function). Crick apparently replied that he hadn't
thought about it before but yes, population geneticists were not
scientists. Dunnett goes on to analyse this and to convince me (or would
have if I hadn't thought it already -- anyone who thought that Motoo Kimura
was not a scientist must be... but maybe I'd better stop there and
charitably assume that Crick hadn't thought it through) that Crick's view
was wrong. I'm quoting this from memory, but I'll try to remember to check
and come back if I'm seriously misrepresenting the book.
Athel
Email: athel at ibsm.cnrs-mrs.fr
Site map: http://ir2lcb.cnrs-mrs.fr/~athel/sitemap.htm
New Beer in an Old Bottle: http://ir2lcb.cnrs-mrs.fr/~athel/buchner.htm
MCA FAQ: http://ir2lcb.cnrs-mrs.fr/~athel/mcafaq.htm
MCA chapter from my book:
http://ir2lcb.cnrs-mrs.fr/~athel/mcai.htm
