The reason the lecture had not been published during Housman's lifetime, and not in its entirety until 1969, was that he had made some statements about a poem of Percy Bysshe Shelley's that he couldn't back up: he'd criticized Algernon Swinburne for gushing over the beauty of a line that, Housman said, was "the verse, not of Shelley, but of a compositor" (33). The poem, titled "A Lament" by Shelley's widow for posthumous publication, seems not to have been completed. Because he couldn't prove his claim, Housman wouldn't allow the lecture to be published, and it would have been lost if his brother Laurence hadn't saved a copy. When it was first published, the section on Shelley's poem was omitted, but eventually the editor John Carter was able to verify from manuscripts that Housman was correct, and the lecture was published unexpurgated (The Confines of Criticism: The Cambridge Inaugural 1911 [Cambridge University Press, 1969]).
It would have stood up well without the discussion of Shelley's poem. I noticed that Housman's epigram about three minutes' thought appears to be a sharpened paraphrase of a saying of Goethe's, which he quotes: "Thinking is hard, and acting according to thought is irksome." (Denken ist schwer, nach dem Gedanken handeln unbequem [37].) A bit later he talks about the way people think:
Not much has changed in the past hundred years -- or in the three centuries before that, as Housman says. The lecture as a whole is a splendid argument for intellectual autonomy, its necessity and its rarity.Men hate to feel insecure; and a sense of security depends much less on the correctness of our opinions than on the firmness with which we hold them; so that by excluding intelligence we can often exclude discomfort. The first thing wanted is a canon of orthodoxy, and the next thing is a pope. The disciple resorts to the teacher, and the request he makes of him is not tell me how to get rid of error but tell me how to get rid of doubt. In this there is nothing new: 'as knowledges are now delivered', said Bacon 300 years ago, 'there is a kind of contract of error between the deliverer and the receiver. For he that delivereth knowledge desireth to deliver it in such form as may be best believed, and not as may be best examined; and he that receiveth knowledge desireth rather present satisfaction than expectant enquiry.' Blind followers of rules will be blind followers of masters: a pupil who has got out of the habit of thinking will take his teacher's word for gospel, and will be delighted with a state of things in which intellectual scrutiny not only ceases to be a duty but becomes an act of insubordination [40-41].