ABSTRACT
323It is a great pleasure to be here in Catalunya and to participate in this meeting on the important subject of the history of physical ideas. I am particularly pleased that this meeting is in a sense dedicated to my old friend Louis Michel. (It has been predicted by Professor Telegdi that some day in the distant future there will be a «station de métro» and even a «boucherie chevaline» named after our colleague, in the tradition of Louis Arago and others. For the moment it is wonderful to have this memorial to Professor Michel while he is still alive.)
