A.J.M. van Gasteren – författare

More than anything else, this book is a tribute to Edsger W. Dijkstra, on the occasion of his sixtieth birthday, by just a few of those fortunate enough to be influenced by him and his work and to be called his friend or relation, his master, colleague, or pupil. This book contains fifty-four technical contributions in different areas of endeavor, although many of them deal with an area of particular concern to Dijkstra: programming. Each contribution is relatively short and could be digested in one sitting. Together, they form a nice cross section of the discipline of programming at the beginning of the nineties. While many know of Dijkstra's technical contributions, they may not be aware of his ultimate goal, the mastery of complexity in mathematics and computing science. He has forcefully argued that beauty and elegance are essential to this mastery. The title of this book, chosen to reflect his ultimate goal, comes from a sentence in an article of his on some beautiful arguments using mathematical induction: "... when we recognize the battle against chaos, mess, and unmastered complexity as one of computing sci- ence's major callings, we must admit that 'Beauty Is Our Business'."

Among all the interests in parallelism, there is an essential and fundamental one that has remained largely unexplored, namely the question of how to design parallel programs from their specification. And that is what this book is about. It proposes a method for the formal development of parallel programs - multiprograms as we have preferred to call them -, and it does so with a minimum of formal gear, viz. with the predicate calculus and with the meanwhile well-established theory of Owicki and Gries. The fact that one can get away with just this theory will probably not convey anything to the uninitiated, but it may all the more come as a surprise to those who were exposed earlier to correctness of multiprograms. Contrary to common belief, the Owicki/Gries theory can indeed be effectively put to work for the formal development of multiprograms, regardless of whether these algorithms are distributed or not. That is what we intend to exemplify with this book.

Among all the interests in parallelism, there is an essential and fundamental one that has remained largely unexplored, namely the question of how to design parallel programs from their specification. And that is what this book is about. It proposes a method for the formal development of parallel programs - multiprograms as we have preferred to call them -, and it does so with a minimum of formal gear, viz. with the predicate calculus and with the meanwhile well-established theory of Owicki and Gries. The fact that one can get away with just this theory will probably not convey anything to the uninitiated, but it may all the more come as a surprise to those who were exposed earlier to correctness of multiprograms. Contrary to common belief, the Owicki/Gries theory can indeed be effectively put to work for the formal development of multiprograms, regardless of whether these algorithms are distributed or not. That is what we intend to exemplify with this book.