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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link="#0563C1" vlink="#954F72"><div class=WordSection1><p class=MsoNormal>Hi, Everybody, and Steve, and Miles<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Please everybody forgive me for what I am about to garble. <o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Steve Guerin and I have a long standing argument concerning the above question. He thinks my answer to the above question will be “natural selection.” His answer to that question is, is that as energy flows from high to low concentrations, it seeks, and finds the most efficient route. Today, steve presented to me a most astounding example, which I am sure most of you are familiar with, but which I had never quite grasped. It is illuminated by a metaphor. Imagine a beach and a lifeguard standing on the beach when a drowning swimmer calls out to the lifeguard’s right. Should the lifeguard run directly toward the drowning swimmer. No, because he can make a lot faster progress toward the swimmer while running on the beach than he can while swimming. So he should chose a path that minimizes his time to the swimmer, not the path directly toward the swimmer. That path, the path of least action, will carry him to the right of the swimmer until he reaches he water’s edge and starts to swim. Lifeguards have to be trained to do this, and lifeguards argue about which direction to head off under under which conditions. <o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Well, light approaching boundary between air and water faces the same situation. And the stunning fact is that light finds the least action path. As I understand it, the light leaves the source in a direction that takes into account the boundary that it is approaching. PLEASE correct me if I have this wrong. Yet, of course, in this situation there is no trial and error. Photons of light just “know” how to do this. If this is true, I promise NEVER to yawn again when one of you is going on about quantum physics. <o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Now, Steve, <span style='font-family:Wingdings'>è</span>IF<span style='font-family:Wingdings'>ç</span> I understood you, you also went on to describe ants behavior and lightening behavior as analogous processes that also find Least Action Pathways. And, I think you are also going to perhaps assert that a tornado is a structure that facilitates a least action pathway. Etc. But these are plainly “historical” processes. I.e, in all cases the process tries out options, and settles on the LAP. But with light, here is no history. Photons are like lifeguards who know instinctively what path to set out on to reach the swimmer with the least action <o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Could I possibly have this right? Once we get this first bit straightened out, I have a question about its relation to natural selection. <o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Nick <o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Nicholas Thompson<o:p></o:p></p><p class=MsoNormal>Emeritus Professor of Ethology and Psychology<o:p></o:p></p><p class=MsoNormal>Clark University<o:p></o:p></p><p class=MsoNormal><a href="mailto:ThompNickSon2@gmail.com">ThompNickSon2@gmail.com</a><o:p></o:p></p><p class=MsoNormal><a href="https://wordpress.clarku.edu/nthompson/">https://wordpress.clarku.edu/nthompson/</a><o:p></o:p></p><p class=MsoNormal> <o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><o:p> </o:p></p></div></body></html>