Churchland, prediction, evolutionary models

John McCreery (JLM@TWICS.COM)
Fri, 15 Sep 1995 10:48:00 +0900

I have been trying to tempt Danny Yee to review Patricia
Churchland's _Neurophilosophy: Toward a unified science
of the mind/brain. In the meantime, I plan over the next
few days to post several quotes from the book which
seem, to me, to speak with unusual eloquence to several
of the issues animating the list. The following is from
Chapter 1, pp. 13-14.

If you root yourself to the ground, you can afford to be
stupid. But if you move, you must have mechanisms for
moving, and mechanism to ensure that the movement is
not utterly arbitrary and independent of what is going on
outside. Consider a simple protochordate, the sea squirt.
The newborn must swim about and feed itself until it
finds a suitable niche, at which time it backs in and
attaches itself permanently. Once attached, the seq
squirt's mechanism for movement become excess
baggage, and it wisely suplements its diet by feasting on
its smartest parts.

Animals are movers, and some of them display
astonishing agility. How is it possible for an owl to dive,
almost silently, out of the night sky and to entrap a
scurrying mouse in its talons? Both organisms are on the
move, yet the owl's timing is precise, and it neither
crashes into the ground nor comes up empty-handed.
How is it possible simply to walk at varying speeds and
over sundry obstacles? Look at a nervous system that is
not performing normally because it has been altered by
drugs, or by disease, or by trauma to the inner ear, for
example, and we get a glimpse of the awesome
complexity that underlies the smooth coordination we
standardly take for granted. What is going on inside a
canary when it learns the motor skill for song production,
or inside wolves when they know how to organize
themselves to bring down a deer? How is it that we see,
hear, and figure things out?

[One paragraph deleted]

In trying to understand the functional principles
governing the human nervous system, we must remind
ourselves that our brain has evolved from earlier kinds
of brains--that our kind of brain was not built from
scratch especially for us, but has capacities and
limitations that are due to its historical origins. The
pressure for nervous systems to evolve has derived not
from the intrinsic beauty of rationality or from some
indwelling goodness attaching to cognition, but primarily
from the need for animals successfully to predict events
in their evironment, including of course events
originating in other organisms....The fundamental nature
of cognition is rooted in the tricks by which assorted
representational schemas give organisms a competitive
advantage in predicting. Representational structures
themselves must be organized to enable informed motor
performance and will bear the stamp of their raison


Churchland herself is concerned to overcome what she
sees as a great and unwarranted conceptual division
between neurobiology on the one hand and cognitive
psychology and philosophy on the other. Her framework
is unabashedly evolutionary and reductionist, but she
shows great sensitivity to the strengths as well as the
weaknesses of competing claims. To Ray Scupin and
others who share our interests in language and cognition,
I would note especially how well Churchland's work
complements George Lakoff's in _Women, Fire and
Dangerous Things_ and thus bears on our recent, back-
channel, discussion of Maurice Bloch. Here is the meat of
the matter, which Bloch only hints at.

Like the Gell-Mann example shared by Ruby Rohrlich,
Churchland's work is superior science by combining a
highly focused eye for detail and a passion for knowing
HOW things happen, with a powerful imagination that
stimulates what may be (mea culpa) totally outrageous
but intriguing ideas.

Consider, for example, the protochordate--the sea squirt
that settles down and devours its now useless "smartest
members." Can we imagine, as another evolutionary
example, a "neolithic stupidity" that sets in with the
founding of fixed, agricultural settlements that require
their members to stay put and devote themselves to
agricultural routine instead of wandering off to new
frontiers. So that, moving to the realm of ideas and
imagination, even seers and shamans then seem to circle
endlessly within the same impoverished cultural worlds?

I said it would be outrageous. Can't wait to see the
answers to this.

John McCreery