As a large number of those stupendous battles that have decided the political and territorial condition of Europe have been fought on the narrow soil of Belgium, so has Germany been for ages the contested field on which were determined the great doctrinal and ecclesiastical questions of the European continent and of the world. Happily, the result has generally been favorable; and let no friend of evangelical truth fear that Rationalism will not meet its merited fate. We must not imagine that, because the term Rationalism has been frequently employed within the last few years, it is of very recent origin either as a word or skeptical type. The Aristotelian Humanists of Helmstedt were called _Rationalists_ in the beginning of the seventeenth century, and Comenius applied the same epithet to the Socinians in 1688.[1] It was a common word in England two hundred years ago. Nor was it imported into the English language from the German, either in a theological or a philosophical sense. There was a sect of Rationalists, in the time of the Commonwealth, who called themselves such exactly on the same grounds as their successors have done in recent years. Some one writing the news from London under date of October 14, 1646, says: "There is a new sect sprung up among them [the Presbyterians and Independents], and these are the _Rationalists, and what their reason dictates them in church or state stands for good until they be convinced with better_."[2] But Rationalists, in fact if not in name, existed on the Continent long anterior to this date. The Anti-Trinitarians, and Bodin, and Pucci were rigid disciples of Reason; and their tenets harmonize with those of a later day.[3] In order to arrive at a proper definition of Rationalism we should consult those authors who have given no little attention to this department of theological inquiry. Nor would we be impartial if we adduced the language of one class to the exclusion of the other. We shall hear alike from the friends and adversaries of the whole movement, and endeavor to draw a proper conclusion from their united testimony. It was Selden's advice to the students of ecclesiastical history, "to study the exaggerated statements of Baronius on the one side, and of the Magdeburg Centuriators on the other, and be their own judges." Fortunately enough for a proper understanding of Rationalism, there is no such diversity of statement presented by our authorities. On the contrary, we shall perceive an unexpected and gratifying harmony.