Re: great chain of being

Phil Nicholls (
Fri, 03 Nov 1995 19:16:17 GMT (H. M. Hubey) graced us with the following
> (Phil Nicholls) writes:

>>What makes an organisms advanced or complex is by comparison to
>>another organism with respect to a specific feature. Humans have very
>>complex brains but rather uncomplicated digestive systems compared to,
>>say, ungulates.

>It looks like I have to get ornery again.


>What complexity measure are you using?

Like most structures in the body, function constraints require tha the
size of the digestive system (total mass of digestive system organs)
maintain a proportional relationship to body size. For mammals we can
take a "mouse to elephant" sample and plot mass of digestive system
against total body mass. Using log scales the relationship becomes
linear, allowing us to fit a line to the data. The line can be said
to represent that proportion of the variability in digestive system
mass accounted for by scaling effects, i.e. differences in complexity
associated with different adaptations.

To gage relative complexity, look at the residuals.

>What measures of complexity are used in PA or bio or related fields?

Depends on the structure involved and what is meant by complexity.

>What kinds of measures of complexity are being used in computer science?

I have never studied computer science or information theory formally.
However if we are talking about instructional information the I
believe that complexity is expressed in terms of the amount of
information and the physical array in which that information exists.

>What kinds of measures of complexity/order/disorder are used in physics?

In thermodynamics the complexity/order/disorder of a system is
expressed as entropy.

>Are there any connections between/amongst any of them in any form?

How many angles can dance on the head of a pin?

>>reference for DNA or the brain as it is at least 15 years out of date.
>>Telling Alex to read _The Dragons of Eden_ is somewhat like telling a

Actually what I said was:

"The Dragons of Eden is a very entertaining work but it not a good
reference for DNA or the brain as it is at least 15 years out of date.
Telling Alex to read _The Dragons of Eden_ is somewhat like telling a
particle physicist to read _The Tao of Physics_ for a reference on
quantum mechanics."

Tell me, why did you delete the first line and the last two lines of
that paragraphy?

>Sagan didn't make up the data. He had original ideas or presented
>them in original ways. Besides, I specifically referred to two
>charts. One of them Info in DNA( and yes the redundancy was
>somewhat taken into account, and it records minimum info) and
>brain/body mass ratio etc.

No you didn't. Here is exactly what you said:

"if you want to talk about complexity and organization, well, this
is the right time, not the time of Darwin. See Carl Sagan,
Dragons of Eden for references to things like information content
of DNA, brain etc.

You are citing Dragons of Eden as a general reference an there is no
mention of a specific charts. As I attempted to point out, it is 15
years out of date. It is also a book written for a lay audience.

>Living things are highly organized and are negentropic (Schrodinger).

"The axiomatic behavior of living systems should be increasing
complexity and self-organization as a result of, not at the expense
of, increasing entropy." Evolution and Entropy: Wiley and Brooks.

Phil Nicholls
"To ask a question you must first know most of the answer"
-Robert Sheckley