All this is still, however, nothing more than psychologic. For the science of religion it accomplishes nothing more than the psychological determination of the peculiarity of the phenomenon, of its environment, its relations and consequences. It is evident that the phenomenon occurs in an indefinite number of varieties; and the chosen point of departure, in unusual and excessive cases, frequently diffuses over religion itself the character of the bizarre and abnormal. Consequently nothing whatever is said about the amount of truth or of reality in these cases. This, by the very principles of such a psychology, is impossible. It analyzes, produces types and categories, points out comparatively constant connections and interactions. But this cannot be the last word for the science of religion. It demands, above all, empirical knowledge of the phenomenon; but it demands this only in order, on the basis of this knowledge, to be able to answer the question of the amount of truth. But this leads to an entirely different problem, that of the theory of knowledge, which has its own conditions of solution. It is impossible to stop at a merely empirical psychology. The question is not merely of given facts, but of the amount of knowledge in these facts. But pure empiricism will not succeed in answering this question. The question with regard to the amount of truth is always a question of validity. The question with regard to validity can, however, be decided only by logical and by general, conceptual investigations. Thus we pass over from the ground of empiricism to that of rationalism, and the question is, what the theory of knowledge or rationalism signifies for the science of religion.
Such a synthesis of the rational and irrational, of the psychological and the theory of knowledge, is the main problem raised by the teaching of Kant, and the significance of Kant is that he clearly and once for all raised the problem in this way. He had the same strong mind for the empirical and actual as for the rational and conceptual elements of human knowledge, and constructed science as a balance between the two. (He destroyed forever the a priori speculative rationalism of the necessary ideas of thought, and the analytical deductions from them, which undertakes to call reality out of the necessity of thought as such. He restricted regressive rationalism to metaphysical hypotheses and probabilities, the evidence for which rests upon the inevitability of the logical operations which leads to them, which, however, apply general concepts without reference to experience, and therefore become empty, and thus afford no real knowledge.) On the other hand, he proclaimed the formal, immanent rationalism of experience, in attempting to unite Hume's truth with the truth of Leibnitz and of Plato. In this way he succeeded in grasping the great problem of thought by the root, and in putting attempts at solutions on the right basis. So it is not a mere national custom of German philosophizing, if we take our bearings, for the most part, from this greatest of German thinkers, but it is, absolutely, the most fruitful and keenest way of putting the problem. It is true, the solutions which Kant made, and which are closely connected with the classical mechanics of that time, with the undeveloped condition of the psychology of that time, and with the incompleteness of historical thinking then just beginning, have been, meantime, more than once given up again. A simple return to him is therefore impossible. But the problem was put by him in a fundamental way, and his solutions need nothing more than modification and completion.
Now all this is especially true in the case of the science of religion. Here also Kant took the same course, which seemed to me right for the theoretical knowledge of the natural sciences and for anthropology. In practical philosophy also, to which he rightly counts philosophy of religion, he seeks laws of the practical reason analogous to the laws of theoretical reason, axioms of the ethical, æsthetic, and religious consciousness which are already contained a priori in the elementary appearances in these fields, and, in application to concrete reality, produce just these activities of the reason. Here also one should grasp reason only as contained in life itself, the a priori law itself already effective in the diversity of the appearances should make one's self clear-sighted and so competent for a criticism of the stream of the soul's appearances. Seizing upon itself in the practical reality, the practical reason criticises the psychological complex, rejects as illusion and error that which cannot be comprehended in an a priori law, selects that part of the same which needs basis and centre and requires only clearness with regard to itself, clears the way for revelations of a life consciousness of its own legality and becomes capable of the development of critically purified experience.
If this is, in principle, valid, the Kantian thought, in the further detail, is maintained in principle only and as a whole. The elaboration itself will have to be quite different from that of his own. Even by Kant himself, on this very point, the synthesis of empiricism and rationalism is far from being elaborated with the necessary rigor and consistency. And to-day we have a quite differently developed psychology of religion, in contrast with which that presupposed by Kant is bare and thin. Finally, there remain in the whole method of the critical system unsolved problems; by failure to solve these, or by too hasty solution, science of religion, especially, is affected.
To make clear the present condition of the problem, one ought, above all, to indicate the modifications to which the Kantian theory of religion must submit,—must submit, especially, by reason of a more delicate psychology, such as we have, with remarkable richness, in James and the American psychologists connected with him. There are four points with regard to this question.
The first is the question of the relation of psychology and theory of knowledge in the very establishment of the laws of the theory of knowledge. Are not the search for and discovery of the laws of the theory of knowledge themselves possible only by way of psychological ascertainment of facts, itself then a psychological undertaking and consequently dependent upon all its conditions? It is the much discussed question of the circle which itself lies at the outset of the critical system. The answer to this is that this circle lies in the very being of all knowledge, and must therefore be resolutely committed. It signifies nothing more than the presupposition of all thought, the trust in a reason which establishes itself only by making use of itself. The unmistakable elements of the logical assert themselves as logical in distinction from the psychological, and from this point on reason must be trusted in all its confusions and entanglements to recognize itself within the psychological. It is the courage of thought, as Hegel says, which may presuppose that the self-knowledge of reason may trust itself, presuppose that reason is contained within the psychological; or it is the ethical and teleological presupposition of all thought, as Lotze says, which believes in knowledge and the validity of its laws for the sake of a connected meaning for reality, and which, therefore, trusts to recognize itself out of the psychological mass. The establishment, therefore, of the laws of the theory of knowledge is not itself a psychological analysis, but a knowledge of self by the logical by virtue of which it extricates itself out of the psychological mass. Theory of knowledge, like every rationalism, includes, it is true, very real presuppositions with regard to the significant, rational, and teleologically connective character of reality, and without this presupposition it is untenable; in it lies its root. It is insight of former days, the importance of which, however, must constantly be emphasized anew, that discusses the validity of the rational as opposed to the merely empirical. But still more important than this thesis are several inferences which are given with it.
The establishment of the laws of consciousness, in which we produce experience, is a selection of the laws out of experience itself, a knowledge of itself by the reason contained in the very experience by way of the analysis which extracts it. It is then an endless task, completed by constantly renewed attacks, and always only approximately solvable. The complete separation of the merely psychological and actual and of the logical and necessary will never be completely accomplished, but will always be open to doubt; one can only attempt always to limit more vigorously the field of what is doubtful. And with this something further is connected.
The inexhaustible production of life becomes constantly, in the latent amount of reason, richer than the analysis discerns, or, in other words, the laws which are brought into the light of logic will always be less the amount of reason not brought into consciousness, and conscious logic will always be obliged to correct itself and enrich itself out of the unartificial logical operations arising in contact with the object. So a finished system of a priori principles, but this system will always be in growth, will be obliged unceasingly to correct itself, and to contain open spaces.
Finally, and above all, in case of this separation, there remains within the psychologically conditioned appearance, a residuum, which is either not conceived, but is later reduced to law and thereby a conceived phenomenon, or which never can be so, and is therefore illusion and error. If the psychological and the theoretical for knowledge are to be separated, then that can occur, not merely to show that both must always be together, and form real experience only when together, but there must also be a rejection of that which is merely psychological and not rational since it is illusion and error. The distinction between the apparent and the real was the point of departure which made the whole theory necessary, and, accordingly, the merely psychological must remain appearance and error side by side with that which is psychological and, at the same time, theoretical for knowledge. There always remains in consciousness a residuum of the inconceivable, that is, inconceivable since it is illusion and error. This amounts to saying that reality is never fully rational, but is engaged in a struggle between the rational and anti-rational. The anti-rational or irrational, in the sense of psychological illusion and error, belongs also to the real, and strives against the rational. The true and rational reality to be attained by thought is always in conjunction with the untrue reality, the psychological, that containing illusion and error.
All this signifies that the rationalism of the theory of knowledge must be conditional, partly owing to the corrective and enriching fecundation by primitive and naïve thought, partly owing to never quite separable admixture of illusion and error. So, long ago, the system of categorical forms, as Kant constructed it for theoretical and practical reason, began to change, and can never again acquire the rigidity which Kant's rationalism intended to give it forevermore. And thus the critical system's rational reality of law produced by reason always contains below itself and beside itself the merely psychological reality of the factual, to which also illusion and error belong,—a reality which can never be rationalized, but only set aside. This, too, is also true for the philosophy of religion: the rational reduction of the psychological facts of religion to the general laws of consciousness which prevail among them is a task constantly to be resumed anew by the study of reality, and follows the movements of primitive religion in order to find there first the rational basis; the reduction is, however, always approximate, can comprehend the main points only, and must leave much open, the rational ground for which is not or not yet evident; finally it has unceasingly to reckon with the irrational as illusion and error, which attaches to the rational, and yet is not explainable by it. The two realities, which the critical system must recognize at its very foundation, continue in strife with each other, and this strife as the strife of divine truth with human illusion is for the science of religion of still more importance.