After all this discussion this morning in UE2 about what is a model, when it came time for the teachers to write in the "model" column of the forms table, both observed tables (2 and 3) were using "model" in a way that I thought was different from what had been worked out in discussion. This time, "model" meant a pedagogical prop. Something you would use to show... what, exactly? Show something having that form of energy? Or just something to point to while you talked about a form of energy, whether it was perceptually apparent that it had that form of energy or not. The systematicity of the things they chose were strange to me - I mean, I don't see the pattern or logic to it. For example, the model for thermal energy could be rubbing hands together, rubbing sticks together, bending a paperclip back and forth, etc. The emphasis seemed to be on ways of producing thermal energy where there was previously "none." While the model for elastic energy was snapping a rubber band. Why snap it? If you wanted to keep the elastic energy, then you would stretch the rubber band and hold it stretched. In any case, this new usage of "model," which the teachers seemed to settle in on fairly quickly and without any explicit negotiation that I noticed, did not seem to fit with or stem from the previous usage of model in the context of the probe. During that discussion, I thought that the focus had been on whether a constructed thing was used for thinking, and whether the thing actually had to be constructed.
My husband the biologist says that in his field, a model is a drawing of the parts of a biological system. I said, "Doesn't a model have to tell you how something works?" and he said in biology the "how it works" IS the picture. The picture is a theory. I think this is part of the whole structure-function thing.
ReplyDeleteThis is just a quick comment about Rachel's comment...
ReplyDeleteI will briefly channel the biology post-doc in our group at Maryland (Julia Svoboda), who has been arguing all year that biologists model in the same way as physicists - that the difference is in what is being modeled but not in the modeling itself. (This was often a response to Joe Redish's frequently stated claim that physicists like to create simplified, stripped down models moreso than biologists do.) Julia often points to evolutionary models or Mendelian genetic models as examples where biologists strip down the actual thing to get a simple (often as unrealistic as frictionless vacuums) model.
She (and I think I) would argue that good scientific modeling is good scientific modeling, irrespective of discipline.