If it is thus indubitable that the views of the world held in earlier times deserve to live on in the memory of man, and to live as something better than mere reminders of the past—­the history of philosophy is not a cabinet of antiquities, but a museum of typical products of the mind—­the value and interest of the historical study of the past in relation to the exact scientific side of philosophical inquiry is not less evident.  In every science it is useful to trace the origin and growth of problems and theories, and doubly so in philosophy.  With her it is by no means the universal rule that progress shows itself by the result; the statement of the question is often more important than the answer.  The problem is more sharply defined in a given direction; or it becomes more comprehensive, is analyzed and refined; or if now it threatens to break up into subtle details, some genius appears to simplify it and force our thoughts back to the fundamental question.  This advance in problems, which happily is everywhere manifested by unmistakable signs, is, in the case of many of the questions which irresistibly force themselves upon the human heart, the only certain gain from centuries of endeavor.  The labor here is of more value than the result.

In treating the history of philosophy, two extremes must be avoided, lawless individualism and abstract logical formalism.  The history of philosophy is neither a disconnected succession of arbitrary individual opinions and clever guesses, nor a mechanically developed series of typical standpoints and problems, which imply one another in just the form and order historically assumed.  The former supposition does violence to the regularity of philosophical development, the latter to its vitality.  In the one case, the connection is conceived too loosely, in the other, too rigidly and simply.  One view underestimates the power of the logical Idea, the other overestimates it.  It is not easy to support the principle that chance rules the destiny of philosophy, but it is more difficult to avoid the opposite conviction of the one-sidedness of formalistic construction, and to define the nature and limits of philosophical necessity.  The development of philosophy is, perhaps, one chief aim of the world-process, but it is certainly not the only one; it is a part of the universal aim, and it is not surprising that the instruments of its realization do not work exclusively in its behalf, that their activity brings about results, which seem unessential for philosophical ends or obstacles in their way.  Philosophical ideas do not think themselves, but are thought by living spirits, which are something other and better than mere thought machines—­by spirits who live these thoughts, who fill them with personal warmth and passionately defend them.  There is often reason, no doubt, for the complaint that the personality which has undertaken to develop some great idea is inadequate to the task, that it carries its subjective defects into the matter in