From the smallest social unit we pass to the largest. A great part of the liberating movement is occupied with the struggle of entire nations against alien rule, with the revolt of Europe against Napoleon, with the struggle of Italy for freedom, with the fate of the Christian subjects of Turkey, with the emancipation of the negro, with the national movement in Ireland and in India. Many of these struggles present the problem of liberty in its simplest form. It has been and is too often a question of securing the most elementary rights for the weaker party; and those who are not touched by the appeal are deficient rather in imagination than in logic or ethics. But at the back of national movements very difficult questions do arise. What is a nation as distinct from a state? What sort of unity does it constitute, and what are its rights? If Ireland is a nation, is Ulster one? and if Ulster is a British and Protestant nation, what of the Catholic half of Ulster? History has in some cases given us a practical answer. Thus, it has shown that, enjoying the gift of responsible government, French and British, despite all historical quarrels and all differences of religious belief, language, and social structure, have fused into the nation of Canada. History has justified the conviction that Germany was a nation, and thrown ridicule on the contemptuous saying of Metternich that Italy was a geographical expression. But how to anticipate history, what rights to concede to a people that claims to be a self-determining unit, is less easy to decide. There is no doubt that the general tendency of Liberalism is to favour autonomy, but, faced as it is with the problems of subdivision and the complexity of group with group, it has to rely on the concrete teaching of history and the practical insight of statesmanship to determine how the lines of autonomy are to be drawn. There is, however, one empirical test which seems generally applicable. Where a weaker nation incorporated with a larger or stronger one can be governed by ordinary law applicable to both parties to the union, and fulfilling all the ordinary principles of liberty, the arrangement may be the best for both parties. But where this system fails, where the government is constantly forced to resort to exceptional legislation or perhaps to de-liberalize its own institutions, the case becomes urgent. Under such conditions the most liberally-minded democracy is maintaining a system which must undermine its own principles. The Assyrian conqueror, Mr. Herbert Spencer remarks, who is depicted in the bas-reliefs leading his captive by a cord, is bound with that cord himself. He forfeits his liberty as long as he retains his power.