Nersessian, N. J. (1992). How do scientists think? Capturing the dynamics of conceptual change in science. In Giere, R. N. (ed.) Cognitive Models of Science. 5--22. University of Minnesota Press. Minneapolis, MN.

@Article{,
  author = 	 {Nersessian},
  title = 	 {How do scientists think? Capturing the
 dynamics of conceptual change in science},
  year = 	 {1998},
  OPTpages = 	 {5--22},
}

Author of the summary: Jim Davies, 2001, jim@jimdavies.org

The actual article is online at: [ PDF]

Cite this paper for:

• The Cognitive-Historical approach
• Conceptual change in science is a problem solving process.[p12]
• Faraday used imagistic representations in theory construction [p14]
• Maxwell used analogy [p21]
• If you create a schema you won't need to use analogy again. [p23]

What great scientists do are refined outgrowths of normal cognition.[p5]

Early philosophers of science borrowed terms from Gestalt psychology. This lead to a view that conceptual change was an abrupt kind of Gestalt switch. Historically, conceptual change is gradual.[p7]

The problem: how are successive scientific conceptualizations of a domain related to each other? Some argue that the concepts are incommensurable and others argue that they grow out of the old concepts. [p8]

The cognitive-historical approach can be used to attack this problem.

Outline of a Cognitive theory of conceptual change [p9]

Kinematics: "how to represent change."
Dymanics: "the processes through which change is created."[p10]

Conceptual structure changes in the following ways:

1. Creation: New concepts are created (e.g. spin)
2. Elimination: Concepts disappear (e.g. phlogiston)
3. Descent: Concepts descend from others, with the same name and different meaning (e.g. mass and field)
4. Absorption: Some absorb attributes of the previous (e.g. ether to field and space-time)

1. If meaning is represented as a set of necessary and sufficient conditions then replacement, not change, is possible.
2. Meaning cannot be represented as a set of necessary and sufficient conditions. Psychological research supports this.

Throughout science history we find use of: [p12]

1. Analogy
   
2. Imagistic Reasoning
   
3. Thought experimentation
   
4. limiting case analysis
   

Wise (1979) argues that Maxwell (1890) used imagery to create the a mathematical representation.[p17]

Maxwell used analogy to make a theory of force processes in ether. Using continuum mechanics as a source, he transferred hypotheses: 1. underlying forces were newtonian 2. "continuity of transmission with the time delay necessary for a field theory" and 3. "unification through finding the mathematical expression for the dynamical relations through which one action gives rise to another." The first was an unsuccessful transfer.[p21]

He broke the problem into subproblems, and made mappings between the electromagnetc and the mechanical properties of a fluid vortex medium. The "mistakes" he made can be explained in terms of model-based reasoning: He, at first, posits that the "displacement current" is going in the wrong direction-- the direction that would be transferred direct in an analogy.

He made an abstract schema so that in the future he wouldn't need to make an analogy. [p23]

Maxwell created a non-newtonian system out of an analogy with a newtonian system.

Summary author's notes:

• none