http://serc.carleton.edu/earthandmind/posts/negativefeedbac.html#discussion http://serc.carleton.edu/earthandmind/posts/negativefeedbac.html#post3672 Callan Bentley 1263651060 http://serc.carleton.edu/earthandmind/posts/negativefeedbac.html#post3672 http://serc.carleton.edu/earthandmind/posts/negativefeedbac.html#post3673 Kim Hannula 1263664500 http://serc.carleton.edu/earthandmind/posts/negativefeedbac.html#post3673 http://serc.carleton.edu/earthandmind/posts/negativefeedbac.html#post3674 Brian Romans 1263665340 http://serc.carleton.edu/earthandmind/posts/negativefeedbac.html#post3674 http://serc.carleton.edu/earthandmind/posts/negativefeedbac.html#post3675
I use the terms "destabilizing" for positive feedback and "stabilizing" (self-regulating)for negative feedback. There is a nice discussion of this, along with some good figures in Merritts, De Wet and Menking, Environmental Geology An Earth System Science Approach, p. 51-52.]]> Dave Mogk 1263828420 http://serc.carleton.edu/earthandmind/posts/negativefeedbac.html#post3675 http://serc.carleton.edu/earthandmind/posts/negativefeedbac.html#post3686 Don Duggan-Haas 1264114620 http://serc.carleton.edu/earthandmind/posts/negativefeedbac.html#post3686 http://serc.carleton.edu/earthandmind/posts/negativefeedbac.html#post13142
I have recently come across a paper that I think provides a way of understanding why this double usage of the same term presents such an obstacle to learning. In a new paper, Gentner (2010) writes about how human's use of language facilitiates our ability to think rigorously and insightfully about the relationships among things, and to recognize that two systems have the same underlying structural relations even though they may look different on the surface. Understanding feedback loops requires exactly this skill: to perceive that a thermostat and a predator-prey relationship have a structural similarity, even though they look totally different from each other.

Among the facilitative mechanisms that Gentner describes is "naming promotes uniform relational encoding." This means that if an individual habitually encounters a specific term for a specific kind of relationship, this increases the chances that the "relational constellation" will be encoded into memory in the same way in different contexts. This in turn tends to foster the development of insights about all the different systems that contain that relationship as the person compares and contrasts the various systems. If the relationship is called by different names in different systems or contexts, the person is more likely to overlook the parallelism between the two systems, and miss out on an important kind of learning that comes from comparing and contrasting.

It seems to me that a corollary of this idea is that if the same relational term is used for different relations in different circumstances or by different people, that this will present an exceptionally enormous obstacle to learning. It violates our expectation that the same relational term will mean the same thing in different systems or contexts. And a learner could waste lots of time and energy and good-will struggling to make a structural mapping between two systems that are fundamentally unaligned and unalignible.

Gentner, D., 2010, Bootstrapping the mind: Analogical processes and symbol systems: Cognitive Science, v. 34, no. 5, p. 752-775. ]]> Kim Kastens 1280953320 http://serc.carleton.edu/earthandmind/posts/negativefeedbac.html#post13142 http://serc.carleton.edu/earthandmind/posts/negativefeedbac.html#post13159 E. Christa Farmer 1283882820 http://serc.carleton.edu/earthandmind/posts/negativefeedbac.html#post13159