Nick having expressed some outrage at what he perceives as (nefarious?) "thread hijacking" (what I prefer to think of as "thread drift", but, hey), I'm starting a new thread.
It seems to me that "thought experiment" (and its German original) is a misleading phrase; further, it seems to me that Nick, of all people, ought to agree with me when I say that the phrase is misleading because it suggests that a "thought experiment" is a particular sort of "experiment", and that the particular sort that it is, is one performed upon reified "thoughts" on the stage of the Cartesian Theatre. What one is actually *doing* (I claim), when conducting a "thought experiment", is much more analogous to calculating than it is to experimentation. (I realize that in a group so loaded with simulators, them's likely to be fighting words; sorry, guys.) It is, in other (maybe better) words, a more-or-less systematic and more-or-less rigorous contemplation of the axioms one has adopted (more or less explicitly), and/or of the formal model one has designed, that is performed with the particular end-in-view of discovering necessary consequences of the axioms/formalities that were not obvious, and that may be surprising or "paradoxical". This description seems to me to fit Einstein's elevator Gedankenexperiment (which I take to be the archetype of thought experiments) perfectly. It fits what Nick called his own "thought experiment", about vortices, less well perhaps--how well it fits depends on how much (if at all) Nick sees in his account of that "thought experiment" what *I* saw jumping out of it, namely, that among his (implicit) axioms are some bits of intuition about physical systems (not too explicitly acknowledged as such) that, coupled with his (more or less) formal model, seem to lead ineluctibly to counter-factual predictions about some actual physical systems. Of course when I put things like that, I can see why someone who has the "key experiment" (is that the phrase? something like it) paradigm always clearly in mind (which I don't), in which the essence of an "experiment" is that it can torpedo a purported theory, might want to say "Yes, a 'thought experiment' is *precisely* a 'type of experiment', you bozo!" Yet I still feel that "thought experiments" are closer to "just-so stories" (except without the negative connotation) than they are to "real experiments" (which *my* intuition says should involve smells, and if possible explosions and huge voltages). Thoughts? Experiments? Lee Rudolph ============================================================ FRIAM Applied Complexity Group listserv Meets Fridays 9a-11:30 at cafe at St. John's College lectures, archives, unsubscribe, maps at http://www.friam.org
