Local Motion or Action-at-a-Distance: The Permanent Debate [RTF Lecture Aug 27]

Date: Sunday Aug. 27 at 2pm Eastern Time

Lecturer: Dr. John Plaice

With the Scientific Revolution of the seventeenth century came the understanding that the same scientific laws govern events in the heavens and on Earth. With this change of outlook came a new problem: How can bodies that are very distant from each other mutually affect their respective motions?

Broadly, two points of view have confronted each other over this question: local motion vs. action-at-a-distance. Over the centuries, philosophers and scientists have taken up one of these positions, trying to explain phenomena as diverse as gravity, magnetism, electricity, weather and quantum effects.

Working through the subtleties of these positions, the following questions have repeatedly recurred: Do atoms exist? Is it possible for a vacuum to exist? Or is there always some sort of medium, plenum or aether? Do (magnetic, electric, gravitational, …) fields exist? And so on.

In this talk, Dr. Plaice will show how this recurring debate addresses the most fundamental questions in the history of science. The talk will consider the opinions of key philosophers and scientists over the centuries, including Plato, Aristotle, Sarpi, Galileo, Kepler, Hobbes, Descartes, Newton, Leibniz, Coulomb, Ampère, Weber, Faraday, Maxwell and Einstein.

Speaker bio: John Plaice is a computer scientist and software engineer. He holds a BMath from the University of Waterloo in Canada, and a PhD and a Habilitation degree from the University of Grenoble in France. He has taught in Canadian and Australian universities, and worked in private industry as a professional software engineer. John Plaice is currently writing a blog, Fiat Lux, on the history of science. Please subscribe at johnplaice.substack.com.