Abstract

I wish to acknowledge my gratitude to Professor James Morrison of the University of Toronto for his encouragement and aid in the preparation of this work. His generosity is an example of the genuine philosophic spirit. I should also like to thank Ernie and Frauke Hankamer as well as Hugo and Ruth Jakusch whose kindness sustained us in Munich and Dieben. Finally, mention must be made of the Canada Council without whose financial aid this book would not have been possible