When I first participated in exploring theories of nonmonotonic reasoning in the late 1970s, I had no idea of the wealth of conceptual and mathematical results that would emerge from those halting first steps. This book by Wiktor Marek and Miroslaw Truszczynski is an elegant treatment of a large body of these results. It provides the first comprehensive treatment of two influen- tial nonmonotonic logics - autoepistemic and default logic - and describes a number of surprising and deep unifying relationships between them. It also relates them to various modal logics studied in the philosophical...

These Proceedings are published to give a full account of the Fifth International Conference on Atmospheric Electricity held in September 1974 in Garmisch-Partenkirchen in the Bavarian Alps in Germany. Traditionally, the Proceedings of these Conferences have served as reference books updating the textbooks and monographs on Atmospheric Electricity. As treated by these Conferences, Atmos pheric Electricity covers all aspects of this science, including the processes and problems which reach out into the Earth's environment as well as analogous processes on other planets and on the Moon. A...

Die alten Vorstellungen, wonach die Erdatmosphare lediglich infolge der darin enthaltenen Gase, die sich an den Atmungsvorgangen in den lebenden Organismen beteiligen, fUr die Aufrechterhaltung und den un gestarten Ablauf des menschlichen Lebens von Bedeutung ist, haben sich durch die Ergebnisse der wissenschaftlichen Forschung in unserem Jahr hundert nicht unwesentlich geandert. Die Erdatmosphare wird nicht mehr als eine Mischung der fur die Atmung notwendigen Gase betrachtet, sondern als ein kompliziert zusammengesetzter Karper, in dem auBer den grundsatzlichen Gaskomponenten auch andere...