Passing over minor writers of the period we are brought to Montesquieu, who about the middle of the 18th century made sev eral monumental contributions to the litera ture of political science, the most notable being his 'Esprit de Lois,> published in 1748, a work which was the result of great study and research. It has been said that his two main ideas were: (1) the construction of a compara tive theory of legislation and institutions adapted to the political needs of different forms of gov ernment ; and (2) a comparative theory of poli tics and law based on wide observation of the actual systems of different lands and ages. He discussed intelligently the various forms of gov ernment, the corruption of democracies, the in fluence upon politics of the elements of air, sun, geography, climate, race, etc. Perhaps the best known and the most permanent in its effects of Montesquieu's political doctrines was his theory of the separation of powers and of checks and balances in government. The idea of the three fold character of governmental powers (legisla tive, executive and judicial) was as old as Aristotle, but it remained for Montesquieu to show that the exercise of each group of these functions by separate and distinct organs was an essential condition of liberty. If all these func tions are exercised by one and the same organ, that is, if the same organ legislates, interprets and executes, its legal sanction is that of a tyrant. This principle was destined to have a large influence upon the political development of the United States and was in the course of time adopted by all the States and by the na tional government.
The last contribution of note in the field of olitical science in the 18th century was that of Jean Jacques Rousseau. This contribution con sisted (1) of his theory of sovereignty and (2) of his theory of the social contract. As opposed to the doctrine of the jurisconsults who held that the will of the prince was law, Rousseau as serted the omnipotence of the people. In the Social,' his most notable work, the theory of the origin of the state as enunciated by Hobbes and Locke was elaborated. Like Locke, Rousseau maintained that presocial men were not in a state of perpetual warfare nor in a con dition of unrestricted license. During the 19th century the names of De Tocqueville in France, Bluntschli in Germany, and Herbert Spencer in England, are perhaps the best known. De Tocqueville's 'Democracy in America> was a philosophical examination of political institu tions in the United States based to some extent on personal observation. Herbert Spencer's 'Political Institutions,' his • 'Principles of Sociology' and his 'Man vs. the State> are substantial contributions to the literature of political science. The individualistic conception of government activity which he sets forth is perhaps the most notable plea for the faire principles to be found anywhere. Blunt schli's 'Theory of the State> is a profound trea tise on the nature and attributes of the state.
In the United States the contributions to political science have, for the most part, been of little consequence. The American mind is practical rather than speculative, and while the Americans have shown great skill in the prepa ration of constitutions and the formulation of rights, they have given little attention to the scientific discussion of the state. Most of the principles of our political science were inherited from England. The ideas of natural rights, popular sovereignty, representation, etc., were the familiar doctrine of the Puritan revolution, while the idea of the separation of powers came from Montesquieu. The first and one of the greatest American treatises on political science was the 'Federalist,> written by Hamilton, Mad ison and Jay in 1788 to secure the adoption of the Constitution. But being a lawyer's brief, it lacks the element of an unbiased philosophical discussion. Thomas Jefferson contributed vari ous ideas of a speculative character, but they never took the form of a systematic treatise and scarcely rose to the dignity of a scientific exami nation of the subjects treated. John C. Cal houn's 'Disquisition on Government,> written in 1850, is an original and profound essay on the nature of government, and has scarcely been surpassed by any other American contnbution in this respect. Two other works deserving of mention are Francis Lieber's 'Political Ethics' and Theodore Woolsey's (Political Science? Lieber's work was the first approach to a sys tematic treatise on political science ever pub lished in America and has had great influence upon the political thought of the nation. His 'Civil Liberty and Self-Government> also oc cupies a distinct place in the literature of the subject. A more valuable treatise still is Woolsey's work first published in 1877 and is without doubt the most scholarly and systematic presentation of the principles of political science which has appeared from the pen of an Ameri can. The most recent contribution is Burgess' Science and Constitutional Law,' which discusses in a profound way the nature and origin of the state, the conception of sovereignty and the relation of government to liberty. Probably no contribution has had such influence in clarifying American conception on these phases of political science.
(See also articles STATE; SovEaEmrrrY; and the sections on Government of the various countries). In addition to the works cited con sult Pollock, 'History of the Science of Poli Seeley, 'Introduction to Political Sci ence' ; Dunning, 'Political Theory of the Ancient or Medkeval World' • Willoughby, 'The Nature of the State' ; also 'Political Theories of the Ancients' ; Garner, 'Introduction to Polit ical Science' ; Leacock, 'Elements of Political Science,' and Gettell, 'Introduction to Political Science.>