I. Dr. Whewell, the founder of the Chair of International Law which I have the honour to occupy in this University, laid the injunction upon every holder of the Chair that he should 'make it his aim,' in all parts of his treatment of the subject, 'to lay down such rules and suggest such measures as may tend to diminish the evils of war and finally to extinguish war between nations.' It is to comply with the spirit, if not with the letter, of this injunction that I have announced the series of three lectures on a League of Nations. The present is the first, and in it I propose to treat of the Aims of the League. But, before I enter into a discussion of these aims, I should like to point out that I have no intention of dealing with the question whether or no a League of Nations should be founded at all. To my mind, and probably to the minds of most of you here, this question has been satisfactorily answered by the leading politicians of all parties and all countries since ex-President Taft put it soon after the outbreak of the World War; it suffices to mention Earl Grey in Great Britain and President Wilson in America. In giving these lectures I propose to draw your attention, on the one hand, to the links which connect the proposal for a League of Nations with the past, and, on the other hand, to the difficulties with which the realisation of the proposal must necessarily be attended; and also to the ways in which, in my opinion, these difficulties can be overcome. There is an old adage which says _Natura non facit saltus_, Nature takes no leaps. Everything in Nature develops gradually, step by step, and organically. It is, at any rate as a rule, the same with History. History in most cases takes no leaps, but if exceptionally History does take a leap, there is great danger of a bad slip backwards following. We must be on our guard lest the proposed League of Nations should take a leap in the dark, and the realisation of proposals be attempted which are so daring and so entirely out of keeping with the historical development of International Law and the growth of the Society of Nations, that there would be great danger of the whole scheme collapsing and the whole movement coming to naught. The movement for a League of Nations is sound, for its purpose is to secure a more lasting peace amongst the nations of the world than has hitherto prevailed. But a number of schemes to realise this purpose have been published which in my opinion go much too far because they comprise proposals which are not realisable in our days. You know that not only an International Court of Justice and an International Council of Conciliation have been proposed, but also some kind of International Government, some kind of International Parliament, an International Executive, and even an International Army and Navy--a so-called International Police--by the help of which the International Government could guarantee the condition of permanent peace in the world.