Collingwood was a historian and Philosopher of note at Oxford, who died in 1943. Here he describes one of his teachers:
"He was a fiery, pugnacious little man with a passion for controversy and an instinctive eye for its tactics; more important, an inspiring teacher, whose enthusiasm for philosophical thought I still remember with admiration and gratitude. He, too, refrained from publication; and he once explained to me his reasons. 'I rewrite, on average, one third of my logic lectures every year', said he. 'That means I'm constantly changing my mind about every point in the subject. If I published, every book I wrote would betray a change of mind since writing the last. Now, if you let the public know that you change your mind, they will never take you seriously. Therefore it is best never to publish at all.' Whether he thought that by not publishing he deceived the public into thinking that he never changed his mind, and whether he regarded this as a good thing to do, even though the public remained ignorant what his mind was, or whether he had a mind at all, I did not ask; probably because I already knew that there are two reasons why people refrain from writing books: either they are conscious that they have nothing to say, or they are conscious that they are unable to say it; and that if they give any other reason than these it is to throw dust in other people's eyes or their own."
R. G. Collingwood, Autobiography (Oxford: Clarendon, 1939), 19.