That turned out to be a perfect lesson for my first research methods lab yesterday. We talked about the sort of "truth" that we do in science (way different from Plato's idea), and how we have to expect change as new data come in.
It also afforded an opportunity to talk about operational definitions, theoretical constructs, and like that. Pluto the object hasn't changed, but the way we conceptualize it has. It was fun (there were the Mickey Mouse/Pluto jokes, too), and very timely. Cheers, m ------- "Whatever power the United States Constitution envisions for the Executive in its exchanges with other nations or with enemy organizations in times of conflict, it most assuredly envisions a role for all three branches when individual liberties are at stake." --- July 20,2006 US District Court for Northern California > -----Original Message----- > From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] > Sent: Friday, August 25, 2006 6:25 AM > To: Teaching in the Psychological Sciences (TIPS) > Subject: [tips] Pluto's chromosomes > > Now that Pluto's been booted out of the solar system, it's > time to reflect. What it reminds me of is a day long ago in > high school. That was the day our biology teacher walked into > class and told us with annoyance that the number of > chromosomes had changed. "They" apparently had decided that > we no longer had 48 chromosomes. We had 46, and that's what > we had to learn from now on. She seemed quite put out about it. > > I now know what that was about. In the early days, it was > very difficult to count human chromosomes because the > preparations were so poor. They were too long and tangled to > count easily, and went in and out of the plane of the > microscope, where they might appear to be two rather than > just one. One of the recognized authorities did a careful > study of them > and reached a conclusion that went something like this: > "Well, sometimes I get 46 chromosomes and sometimes I get 48. > I can't be sure, but maybe the 48 count is the best estimate". > > Over time, that n = 48 number became reified, and people > forgot about the doubts expressed in the original paper. > Instead, whenever they counted chromosomes and got 46, they > said "Nah, couldn't be", and counted again. > They kept counting until they got the right answer, which > they knew was 48. And the 48 number would be confirmed. > > Finally, chromosomal preparations improved so much that it > became blindingly obvious that there were only 46, and at > last one brave soul said so. Eventually it filtered down to > the high school textbook level. > Enter my teacher. > > So the moral seems to be that science does change (see > Pluto). But more attention to the primary literature, and to > the data, not to mention to using an appropriate technique to > avoid contaminating results with expectations wouldn't hurt. > Also, it wouldn't hurt to have less respect for authority. > > Stephen > > ----------------------------------------------------------------- > Stephen L. Black, Ph.D. > Department of Psychology > Bishop's University e-mail: [EMAIL PROTECTED] > 2600 College St. > Sherbrooke QC J1M 0C8 > Canada > > Dept web page at http://www.ubishops.ca/ccc/div/soc/psy > TIPS discussion list for psychology teachers at > http://faculty.frostburg.edu/psyc/southerly/tips/index.htm > -------------------------------------------------------------- > --------- > > --- > To make changes to your subscription go to: > http://acsun.frostburg.edu/cgi-bin/lyris.pl?enter=tips&text_mo > de=0&lang=english > > --- To make changes to your subscription go to: http://acsun.frostburg.edu/cgi-bin/lyris.pl?enter=tips&text_mode=0&lang=english
