Philosopher, polymath, and pre-scientist. He was an early critic of the inhibiting effect of authorities on thought, and an early exponent of empiricism, logic, the experimental method in science, along with the encouragement of technology and invention. Given these attitudes, his decision at age forty-one to join the Franciscan Order was a tragic error, since the Franciscans were even less receptive to his work than other orders might have been. He was silenced, then permitted by the Papacy to write specifically for the Pope, then imprisoned by the Order for fourteen years, after which he died.