ment of national life had not centred in the monarchy. The centrifugal forces of interest-the desire for peace, good government, facilities for commerce, and so forth -obtained free play under the imperial administration, and to these was added after a time the sense of pride in Roman citizenship, and in the greatness of a State which included all the highest civilization of the world. So too during the Middle Ages not a few conquests ended in an assimilation of the vanquished, which enlarged without weakening the conquering nation. But during the last three centuries the experience of military powers has been that the acquisition of masses of subjects who, being already civilized, are likely to resist absorption and to remain disaffected, is a doubtful gain and may become a danger to the conquering State. The last conspicuous instance is Poland, partitioned between three Powers, to all of whom her provinces have brought trouble. Conquests continue to be made, but they are now mostly of barbarous or semi-civilized races, so inferior to the conquerors in force and in national spirit that the centrifugal forces are, or at least seem to be, practically negligible.

Is it possible, then, to arrive at any conclusion regarding the respective strength which these two sets of forces are likely to display in the coming centuries? Will the tendency to aggregation continue, and does the future belong to great States? Or may new forces appear which will reverse the process, as it was

in the modern sense; and the Roman system left most of them a certain measure of self-government which modified their regret for an independence the delight in which had been (in many cases) reduced by domestic disorders.

reversed, though through causes most unlikely to reappear, at the fall of the Roman Empire ?

At first sight the probabilities seem to point to further aggregation. Although none of the five great national States-Russia, Germany, France, Italy, Britain-is in the least likely to be absorbed by any of the others, there is reason to think that within the next century some of the smaller states will have disappeared from the map of Europe. In one or two other parts of the world-as for instance in South and in Central America-the process by which the great States are expanding is not yet complete. The influences of swifter and cheaper communications by land and sea, of increasing commerce, and of the closer intercourse which commerce brings, of the power exerted by the printing press in extinguishing the languages which prevail over a small area and diffusing those spoken by vast masses of men—all these things make for unity within each of the great States and add to the attractive power which the greater have for the smaller. These influences, moreover, all promise to be permanent.

Against them we must set the fact that Conquest, so far as civilized peoples are concerned, seems likely to play a smaller rôle in the future than in the past, because it begins to be perceived how tenacious is the sentiment of nationality in a vanquished people, and how much the maintenance of that sentiment may endanger the victor State. As was observed in an earlier page, the progress of a community in civilization often tends to intensify both its capacity for political discontent and its peculiar national sentiment, thus

counterworking the influences of trade and wealth. A people, or a nationality included in a large State, while feeling the centripetal forces of material interest, may nevertheless feel the repellent instinct of an unquenched attachment to its national traditions and cling to the hope of reviving its old national life.

The problem is, however, a far more complex one than any comparison of the influences of material interest on the one side and national sentiment on

the other would suggest. Many phenomena may be imagined which would affect it as the world moves on. One is a change in the conditions under which war is waged. Another is a removal of some of the causes which induce war, or a means, better than now exists, of averting its outbreak. Another is the growth of what is called Collectivism and a disposition to apply its principles in small rather than in large areas, seeing that there are obviously some things which can be better managed in the former. We are far from having exhausted the possibilities of the influence of scientific discovery upon economic life, and through it upon social and political life. Both the relations of Nations and States to one another and the relations of the groups or communities within each State to each other may be affected in ways as yet scarcely dreamt of. Neither can we foresee the modes in which the scientific way of looking at all questions may come ultimately to tinge and modify men's habits of thought even in social and political matters. No institution was at one time more generally prevalent over the world, or seemed more deeply rooted, than Slavery; and slavery, which has now vanished from civilized communities,

will soon have vanished from all countries. There is indeed hardly any institution for which permanence can be predicted except-and some will not admit even this exception-the Family.

Imagine a world in which all the hitherto unappropriated territories had been allotted to one or other of the few strongest States. Imagine tariffs abolished and the principle of equality of trade-facilities among States established. Imagine a system of international arbitration created under which the risks of war were so greatly reduced that the prospect of war did not occupy men's minds and give a military and aggressive tinge to their patriotism. The present relations of centripetal and centrifugal forces would under such conditions be greatly altered, as respects both the wide theatre of the world and the internal conditions of each particular State.

Imagine also a great advance in the desire to use governmental agencies for the benefit of the citizens, and a general conviction that such agencies could best be used by comparatively small communities rather than by the State as a whole. A new centrifugal force, centrifugal at least in respect of each State, would thereby have been called into action. No one will venture to foretell any of these things. But none of them is impossible; and it is plain that they might produce a set of conditions, and a play of forces, unlike the present, and unlike any period in the past. We must not therefore assume that the large States and the present structure and organization of States will be permanent.

Of the more remote future, History can venture to say

little more than this-that it will never bring back the past. She recognizes that, as Heraclitus says, one cannot step twice into the same river. Even when she is able to declare that certain forces will assuredly be present, she cannot forecast their relative strength at any given moment, nor say what hitherto unobserved forces they may not, in their action upon one another, call into activity. All she can do for the lawyer, the statesman and the legislator, when they have to study and use the forces operative in their own time, is to indicate to them the nature and the character, the significant elements of strength and weakness, that belong to each and every force that has been heretofore conspicuous, so as to direct and guide them in observing and reflecting on the present. This is much less than has sometimes been claimed for history. Nevertheless it is a real service, for nothing is more difficult than to observe exactly, and the ripest fruit of historical study is that detachment of mind, created by the habit of scientific thinking, which prevents observation from being coloured by prejudice or passion.