To this last proposition there is, however, an important exception to be made in favour of men of genius, who are commonly at once representative and creative. They embody and reflect the tendencies of their time, but they also frequently materially modify them, and their ideas become the subject or the basis of the succeeding developments. To trace in every great movement the part which belongs to the individual and the part which belongs to general causes, without exaggerating either side, is one of the most delicate tasks of the historian.
What I have written will, I trust, be sufficient to show the distinction between the sphere of the historian and the sphere of the theologian. It must, however, be acknowledged that they have some points of contact; for it is impossible to reveal the causes that called an opinion into being without throwing some light upon its intrinsic value. It must be acknowledged, also, that there is a theory or method of research which would amalgamate the two spheres, or, to speak more correctly, would entirely subordinate the theologian to the historian. Those who have appreciated the extremely small influence of definite arguments in determining the opinions either of an individual or of a nation—who have perceived how invariably an increase of civilisation implies a modification of belief, and how completely the controversialists of successive ages are the puppets and the unconscious exponents of the deep under-current of their time, will feel an intense distrust of their unassisted reason, and will naturally look for some guide to direct their judgment. I think it must be admitted that the general and increasing tendency, in the present day, is to seek such a guide in the collective wisdom of mankind as it is displayed in the developments of history. In other words, the way in which our leading thinkers, consciously or unconsciously, form their opinions, is by endeavouring to ascertain what are the laws that govern the successive modifications of belief; in what directions, towards what conceptions, the intellect of man advances with the advance of civilisation; what are the leading characteristics that mark the belief of civilised ages and nations as compared with barbarous ones, and of the most educated as compared with the most illiterate classes. This mode of reasoning may be said to resolve itself into three problems. It is necessary, in the first place, to ascertain what are the general intellectual tendencies of civilisation; it is then necessary to ascertain how far those tendencies are connected, or, in other words, how far the existence of one depends upon and implies the existence of the others; and it is necessary, in the last place, to ascertain whether they have been accompanied by an increase or diminution of happiness, of virtue, and of humanity.
My object in the present work has been, to trace the history of the spirit of Rationalism; by which I understand, not any class of definite doctrines or criticisms, but rather a certain cast of thought, or bias of reasoning, which has during the last three centuries gained a marked ascendency in Europe. The nature of this bias will be exhibited in detail in the ensuing pages, when we examine its influence upon the various forms of moral and intellectual development. At present, it will be sufficient to say, that it leads men on all occasions to subordinate dogmatic theology to the dictates of reason and of conscience, and, as a necessary consequence, greatly to restrict its influence upon life. It predisposes men, in history, to attribute all kinds of phenomena to natural rather than miraculous causes; in theology, to esteem succeeding systems the expressions of the wants and aspirations of that religious sentiment which is planted in all men; and, in ethics, to regard as duties only those which conscience reveals to be such.
It is manifest that, in attempting to write the history of a mental tendency, some difficulties have to be encountered quite distinct from those which attend a simple relation of facts. No one can be truly said to understand any great system of belief, if he has not in some degree realised the point of view from which its arguments assume an appearance of plausibility and of cogency, the habit of thought which makes its various doctrines appear probable, harmonious, and consistent. Yet, even in the great controversies of the present day—even in the disputes between the Catholic and the Protestant, it is evident that very few controversialists ever succeed in arriving at this appreciation of the opinions they are combating. But the difficulty becomes far greater when our research extends over forms of belief of which there are no living representatives, and when we have not merely to estimate the different measures of probability subsisting in different societies, but have also to indicate their causes and their changes. To reconstruct the modes of thought which produced superstitions that have long since vanished from among us; to trace through the obscurity of the distant past that hidden bias of the imagination which—deeper than any strife of arguments, deeper than any change of creed—determines in each succeeding age the realised belief; to grasp the principle of analogy or congruity according to which the conceptions of a given period were grouped and harmonised, and then to show how the discoveries of science, or the revolutions in philosophy, or the developments of indus trial or political life, introduced new centres of attraction, and made the force of analogy act in new directions; to follow out the process till the period when conclusions the reason had once naturally and almost instinctively adopted seem incongruous and grotesque, and till the whole current of intellectual tendencies is changed:—this is the task which devolves upon every one who, not content with relating the fluctuations of opinions, seeks to throw some light upon the laws that govern them.
Probably, the greatest difficulty of such a process of investigation arises from the wide difference between professed and realised belief. When an opinion that is opposed to the age is incapable of modification and is an obstacle to progress, it will at last be openly repudiated; and if it is identified with any existing interests, or associated with some eternal truth, its rejection will be accompanied by paroxysms of painful agitation. But much more frequently civilisation makes opinions that are opposed to it simply obsolete. They perish by indifference, not by controversy. They are relegated to the dim twilight land that surrounds every living faith; the land, not of death, but of the shadow of death; the land of the unrealised and the inoperative. Sometimes, too, we find the phraseology, the ceremonies, the formularies, the external aspect of some phase of belief that has long since perished, connected with a system that has been created by the wants and is thrilling with the life of modern civilisation. They resemble those images of departed ancestors, which, it is said, the ancient Ethiopians were accustomed to paint upon their bodies, as if to preserve the pleasing illusion that those could not be really dead whose lineaments were still visible among them, and were still associated with life. In order to appreciate the change, we must translate these opinions into action, must examine what would be their effects if fully realised, and ascertain how far those effects are actually produced. It is necessary, therefore, not merely to examine successive creeds, but also to study the types of character of successive ages.
It only remains for me, before drawing this introduction to a close, to describe the method I have employed in tracing the influence of the rationalistic spirit upon opinions. In the first place, I have examined the history and the causes of that decline of the sense of the miraculous, which is so manifest a fruit of civilisation. But it soon becomes evident that this movement cannot be considered by itself; for the predisposition in favour of miracles grows out of, and can only be adequately explained by, certain conceptions of the nature of the Supreme Being, and of the habitual government of the universe, which invariably accompany the earlier, or, as it may be termed, the anthropomorphic stage of intellectual development. Of the nature of this stage we have some important evidence in the history of art, which is then probably the most accurate expression of the religious realisations; while the history of the encroachments of physical science upon our first notions of the system of the world, goes far to explain its decay Together with the intellectual movement, we have to consider a moral movement that has accompanied it, which has had the effect of diminishing the influence of fear as the motive of duty, of destroying the overwhelming