EdsgerWybeDijkstra was one of the pioneers of ComputerScience and renowned for the insight that mathematical logic is and must be the basis for sensible computer program construction. He was a large force in developing mathematical methodology in ComputerScience and responsible for the idea of building OperatingSystems as explicitly synchronized sequential processes.
It is only consequent that one of his most well known papers is GoToStatementConsideredHarmful, but he also wrote over thirteen hundred other works, all using the fountain pen rather than a computer, which are archived in digital form at http://www.cs.utexas.edu/users/EWD.
"The question of whether computers can think is like the question of whether submarines can swim."
"Do only what only you can do." (In advice to a promising researcher who asked how to select a topic for research.)
He was uncompromisingly critical of everything. Few of his known quotations are good words. Just look at some of them by following the BackLinks for this page.
Of note is that he was citizen of both the Netherlands, where he was born, as well as of the US. His actual first name is Edsger, while in America he is often called Edgar.