Here is a link to Alan's talk, his reference to Eratostenes starts at around 51:50.
Alan, do you still have a copy of the presentation? Stephen On Thu, Sep 29, 2011 at 12:18 AM, Alan Kay <alan.n...@yahoo.com> wrote: > But consider a flat Earth and a low small sun directly over the well. This > will yield exactly Eratosthenes' result. The key here, which I've never seen > mentioned in any books for children, is that the Greeks had to have a very > good set of reasons for thinking the Earth round and the sun large enough > and far enough away (and they did). > > I gave a talk on how they did this in the Kyoto Prize lecture followups in > San Diego in 2005. Aristarchus was one of several key figures. > > The shame of it is that for both math and science learning, the important > heuristic of trying to identify all the possible cases for a result is never > encountered by the children (or most adults) who have read about > Eratosthenes. > > Cheers, > > Alan > > ------------------------------ > *From:* Steve Thomas <sthom...@gosargon.com> > *To:* naturalm...@googlegroups.com; iaep <iaep@lists.sugarlabs.org>; > squeakland <squeakl...@squeakland.org> > *Sent:* Wednesday, September 28, 2011 9:06 PM > *Subject:* [NaturalMath] KIds from around the world measuring the > Circumference of the Earth > > The Goal of the Noon Day Project <http://ciese.org/curriculum/noonday/> is > to have students measure the circumference of the earth using a method that > was first used by Eratosthenes over 2000 years ago. > Students at various sites around the world will measure shadows cast by a > meter stick and compare their results. > From this data students will be able to calculate the circumference of the > earth. Click here to get to their site and > register.<http://ciese.org/curriculum/noonday/> > > Watch the Carl Sagan video, <http://youtu.be/0JHEqBLG650> its a treat. > > Thanks to Ihor Charischak for pointing this out. > > Stephen > -- > You received this message because you are subscribed to the Google Groups > "NaturalMath" group. > To post to this group, send email to naturalm...@googlegroups.com. > To unsubscribe from this group, send email to > naturalmath+unsubscr...@googlegroups.com. > For more options, visit this group at > http://groups.google.com/group/naturalmath?hl=en. > > > > _______________________________________________ > IAEP -- It's An Education Project (not a laptop project!) > IAEP@lists.sugarlabs.org > http://lists.sugarlabs.org/listinfo/iaep >
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