The semantic engineer
Daniel Dennett took on the grandees of philosophy while still a student at Harvard and Oxford, then turned to pioneering and controversial work on artificial intelligence. With Richard Dawkins he has fought the 'Darwin Wars' and, when not sailing or farming, sculpting or playing jazz, is writing a new book opposing the rise of supernaturalism.
Postscript: Dennett has pointed out a number of minor errors in this article to its author (Andrew Brown), who has listed them on his website.