Shall we not say, then, that this double-faced but wholly true lesson has been learned: namely, that the so-called philosophy of nature has no sound foundation and no safeguard against vagaries of every sort, unless it follows the lead of the positive sciences of nature; but that the sciences themselves can never afford a full satisfaction to the legitimate aspirations of human reason unless they, too, contribute to the philosophy of nature--writ large and conceived of as a real-ideal Unity.
That nature, as known and knowable by man, is a great artist, and that man's æsthetical consciousness may be trusted as having a certain ontological value, is the postulate properly derived from the considerations advanced in the latest, and in some respects the most satisfactory, of the three Critiques of Kant. The ideal way of looking at natural phenomena which so delighted the mind of Goethe has now been placed on broad and sound foundations by the fruitful industries of many workmen,--such as Karl Ernst von Baer and Charles Darwin,--whose morphological and evolutionary conceptions of the universe have transformed the current conceptions of cosmic processes. But the world of physical and natural phenomena has thereby been rendered not less, but more, of a Cosmos, an orderly totality.
In addition to these more general but somewhat vague evaluations of the progress of philosophy during the nineteenth century, we are certainly called upon to face the question whether, after all, any advance has been made toward the more satisfactory solution of the definite problems which the Kantian criticism left unsolved. To this question I believe an affirmative answer may be given in accordance with the facts of history. It will be remembered that the first of these problems was the epistemological. Certainly no little improvement has been made in the psychology of cognition. We can no longer repeat the mistakes of Kant, either with respect to the uncritical assumptions he makes regarding the origin of knowledge in the so-called "faculties" of the human mind or regarding the analysis of those faculties and their interdependent relations. It is not the Scottish philosophy alone which has led to the conclusion that, in the word of the late Professor Adamson, "What are called acts or states of consciousness are _not_ rightly conceived of as having for their objects their own modes of existence as ways in which a subject is modified." And in the larger manner both science and philosophy, in their negations and their affirmations, and even in their points of view, have better grounds for the faith of human reason in its power progressively to master the knowledge of Reality than was the case a hundred years ago. Nor has the skepticism of the same era, whether by shallow scoffing at repeated failures, or by pious sighs over the limitations of human reason, or by critical analysis of the cognitive faculties "according to well-established principles," succeeded in limiting our speculative pretensions to the sphere of possible experience,--in the Kantian meaning both of "principles" and of "experience." But what both science and philosophy are compelled to agree upon as a common underlying principle is this: The proof of the most fundamental presuppositions, as well as of the latest more scientifically established conclusions, of both science and philosophy, is the assistance they afford in the satisfactory explanation of the totality of racial experience.