Thus renovated, the theory of knowledge seems destined to unite the opposing advantages of the two rival theories, without incurring their inconveniences. It keeps all the essential principles of the apriorists; but at the same time it is inspired by that positive spirit which the empiricists have striven to satisfy. It leaves the reason its specific power, but it accounts for it and does so without leaving the world of observable phenomena. It affirms the duality of our intellectual life, but it explains it, and with natural causes. The categories are no longer considered as primary and unanalysable facts, yet they keep a complexity which falsifies any analysis as ready as that with which the empiricists content themselves. They no longer appear as very simple notions which the first comer can very easily arrange from his own personal observations and which the popular imagination has unluckily complicated, but rather they appear as priceless instruments of thought which the human groups have laboriously forged through the centuries and where they have accumulated the best of their intellectual capital.[24] A complete section of the history of humanity is resumed therein. This is equivalent to saying that to succeed in understanding them and judging them, it is necessary to resort to other means than those which have been in use up to the present. To know what these conceptions which we have not made ourselves are really made of, it does not suffice to interrogate our own consciousnesses; we must look outside of ourselves, it is history that we must observe, there is a whole science which must be formed, a complex science which can advance but slowly and by collective labour, and to which the present work brings some fragmentary contributions in the nature of an attempt. Without making these questions the direct object of our study, we shall profit by all the occasions which present themselves to us of catching at their very birth some at least of these ideas which, while being of religious origin, still remain at the foundation of the human intelligence. BOOK I PRELIMINARY QUESTIONS CHAPTER I DEFINITION OF RELIGIOUS PHENOMENA AND OF RELIGION[25]