Biology and Physics

My messages to the everything-list

28.01.2012 13:04:

Let my quote Jeffery A. Gray, (Consciousness: Creeping up on the Hard Problem p. 33) on biology and physics.

“In very general terms, biology makes use of two types of concept: physicochemical laws and feedback mechanisms. The latter include both the feedback operative in natural selection, in which the controlled variables that determine survival are nowhere explicitly represented within the system; and servomechanisms, in which there is a specific locus of representation capable of reporting the values of the controlled variables to other system components and to other systems. The relationship between physicochemical laws and cybernetic mechanisms in the biological perspective on biology poses no deep problems. It consist in a kind of a contract: providing cybernetics respects the laws of physics and chemistry, its principles may be used to construct any kind of feedback system that serves a purpose. Behaviour as such does not appear to require for its explanation any principles additional to these.”

Roughly speaking Gray’s statement is

Biology = Physics + Feedback mechanisms

Yet even at this stage (just at a level of bacteria, I guess there is no qualia yet) it is unclear to me whether physics includes cybernetics laws or they emerge/supervene. What is your opinion to this end?

29.01.2012 17:56:

The quote above was from the beginning of Gray’s book where he tries to consider life and a human being from the viewpoint of physicalism. Yet, he shows later on that this does not work and consciousness remains as a hard problem.

29.01.2012 18:02:

Basically the cybernetics laws describe a feedback. Let us for a example consider a PID controller to keep the temperature constant in a thermostat. What is the relationship between the equations implemented in the controller and physics laws? Do these equations emerge from or supervene to the physics laws?

01.02.2012 21:20:

I think that there is some difference in respect that one can abstract control from a particular application. For example, I can consider a PID controller as such. Such a consideration belongs, roughly speaking, to cybernetics laws.