  There are many reasons for this interest, but one is that in every sphere of his life and work he made unexpected connections between apparently unrelated areas. His central contribution to science and philosophy came through his treating the subject of symbolic logic as a new branch of applied mathematics, giving it a physical and engineering content. Unwilling or unable to remain within any standard role or department of thought, Alan Turing continued a life full of incongruity. Though a shy, boyish, man, he had a pivotal role in world history through his role in Second World War cryptology. Though the founder of the dominant technology of the twentieth century, he variously impressed, charmed or disturbed people with his unworldly innocence and his dislike of moral or intellectual compromise.