The history of the modern world is a record of highly varied activity, of incessant change, and of astonishing achievement. The lives of men have, during the last few centuries, increasingly diversified, their powers have greatly multiplied, their powers have greatly multiplied, their horizon been enormously enlarged. New interests have arisen in rich profusion to absorb attention and to provoke exertion. New aspirations and new emotions have come to move the soul of men. Amid all the bewildering phenomena, interest, in particular, has stood out in clear and growing pre-eminence, has expressed itself in a multitude of ways and with an emphasis more and more pronounced, namely, the determination of the race to gain a larger measure of freedom than it has ever known before, freedom in the life of the intellect and spirit, freedom in the realm of government and law, freedom in the sphere of economic and social relationship. A passion that has prevailed so widely, that has transformed the world so greatly, and is still transforming it, is one that surely merits study and abundantly rewards it, its operations constitute the very pith and marrow of modem history.
Not that this passion was unknown to the long ages that proceeded the modern periods. The ancient Hebrews, the ancient Greeks and Roman blazed the was leaving behind them a precious heritage of accomplishments and suggestions and the men who were responsible for the Renaissance of the fifteenth century and the Reformation of the sixteen century contributed their imperishable part to this slow and difficult emancipation of the human race. But it is in modern times the pace and vigour, the scope and sweep of this liberal movement have so increased unquestionably as to dominate the age, particularly the last three centuries that have registered great triumphs of spirit.
The operation of which factor constitutes the pith and marrow of modern history?