This yearly commemoration of Martin Wight by means of a lecture is doubly appropriate. An annual lecture keeps his memory green among his friends and pupils. And in the second place, it is a peculiarly fitting celebration because Martin Wight was a teacher whose greatest and most seminal influence was in large measures exercised in lectures tutorials, seminars and discussion groups. Exercised that is by means of the spoken, the living, word transmitted directly person to person, mind to mind. When it is contrasted with, say, a book, mere speech is thought to be something fleeting and evanescent, not to be compared with the tangibility, fixity, durability of the written and the printed word. But this is the merest superstition, for that which is fixed is also dead and inert. If the written word has power to speak to us, to move us, this is because it is the emanation and the embodiment of the living spirit. I am, here, put in mind of a striking passage which occurs in that most moving of Plato's writings, the writing known as the seventh epistle – a passage where Plato describes how his teaching is transmitted. This teaching he declares is not to be found in anything written down. The knowledge with which he is concerned is of the kind which “after long-continued intercourse between teacher and pupil, in joint pursuit of the subject, suddenly, like light flashing forth when a fire is kindled, it is born in the soul and straightway nourishes itself. ”The light of Martin Wight's discourse, its rayonnement, an irradiation now felt by many who never knew or met him – it is this which has brought us together on this occasion, and which illuminates the issues I am about to consider – issues which we have reason to believe interested him closely, and in more ways than one.