The proposition that governments exist for the benefit of the governed, and not merely for the advantage of those who exercise the powers of government, is not original with the American people. It had been recognized as fundamental by many writers before the Revolution, and is a necessary outcome of the fact demonstrated by human experience, that as between a single ruler, or a small ruling class, and the mass of the people who are ruled, the great preponderance of power and resource is with the latter. This consideration has made it essential that all rulers or governing classes shall at least pretend to administer government for the benefit of the governed. The tendency of civilization towards the betterment of the people as a whole, and the recognition by Christianity of the individual as entitled to consideration on his own account as a human being, have co-operated with the primary necessity of recognizing the welfare of the governed, in bringing about a constant pressure for the improvement of government and of the institutions which are supported or recognized by government. The result in human history has been to produce changes, more or less gradual, in government and institutions; so that in any state or nation a system of government, and the institutions existing under it, must be regarded as the result of a development due to the action of this constant pressure.

Human institutions must be studied in the light of their historical origins and progress. They do not spring into existence spontaneously without relation to that which has gone before: they are not the result of conscious creation. New conceptions or ideals on the part of those who have controlling influence in shaping institutions may result in modifications, and new circumstances or conditions almost certainly lead to changes. But changes will necessarily be gradual, and usually by adapting to the new conditions that which is in existence. This will be peculiarly true under a system of government recognizing a distribution or division of powers among several departments.

Revolutions in society or government are usually found on examination to be more apparent than real. Changes, no matter how radical or sudden, commonly spring out of causes having a connected and definite history. In a government in which a considerable portion of the people exercise a controlling influence, changes in form as well as in substance will be gradual; or if sudden, the institutions which most nearly affect the general welfare will alter least and most slowly.

The people of the colonies of Great Britain in America who, by declaring their independence and organizing state governments and subsequently the federal government as it now exists, laid the foundations and determined the form of our present system, were for the most part of English descent, and before independence was declared were British subjects claiming rights which they believed themselves entitled to as such subjects. The governments of the colonies derived their authority from the British crown; the institutions prevailing in the colonies were almost wholly British institutions, the history of which is to be traced in the history of the people of Great Britain; and the theories of government prevailing were such as were familiar to English people, modified, however, to meet the new conditions under which the colonists lived. To understand our institutions and the principles of our government, constant recourse must be had to the government and institutions of Great Britain as they existed just prior to and during the colonial period. The constitutional history of Great Britain will therefore furnish a basis for the comprehension of the constitutional history of the United States.

Constitutional history is, however, to be distinguished from constitutional law. By the latter term is meant the body of rules and principles in accordance with which the powers of government are exercised. To understand the development of those rules and principles, and their origin, and true nature, it is necessary to look to constitutional history; but the determination, with such definiteness as is practicable, of what those rules and principles actually are at the present time, is within the province of constitutional law. These rules and principles are not to be understood, however, without constant reference to the course of their development, and constitutional law is therefore dependent upon constitutional history.