and its identity is found, not in isolation, but in continuity and sovereignty. This it is that imparts to the history both of states and of religions, its specially turbulent and polemical character. Such is the explanation of the wranglings, whether of schools or of parliaments. It is the warfare of ideas under their various aspects striving for the mastery, each of them enterprising, engrossing, imperious, more or less incompatible with the rest, and rallying followers or rousing foes, according as it acts upon the faith, the prejudices, or the interest of parties or classes. 6. Moreover, an idea not only modifies, but is modified, or at least influenced, by the state of things in which it is carried out, and is dependent in various ways on the circumstances which surround it. Its development proceeds quickly or slowly, as it may be; the order of succession in its separate stages is variable; it shows differently in a small sphere of action and in an extended; it may be interrupted, retarded, mutilated, distorted, by external violence; it may be enfeebled by the effort of ridding itself of domestic foes; it may be impeded and swayed or even absorbed by counter energetic ideas; it may be coloured by the received tone of thought into which it comes, or depraved by the intrusion of foreign principles, or at length shattered by the development of some original fault within it. 7. But whatever be the risk of corruption from intercourse with the world around, such a risk must be encountered if a great idea is duly to be understood, and much more if it is to be fully exhibited. It is elicited and expanded by trial, and battles into perfection and supremacy. Nor does it escape the collision of opinion even in its earlier years, nor does it remain truer to itself, and with a better claim to be considered one and the same, though externally protected from vicissitude and change. It is indeed sometimes said that the stream is clearest near the spring. Whatever use may fairly be made of this image, it does not apply to the history of a philosophy or belief, which on the contrary is more equable, and purer, and stronger, when its bed has become deep, and broad, and full. It necessarily rises out of an existing state of things, and for a time savours of the soil. Its vital element needs disengaging from what is foreign and temporary, and is employed in efforts after freedom which become more vigorous and hopeful as its years increase. Its beginnings are no measure of its capabilities, nor of its scope. At first no one knows what it is, or what it is worth. It remains perhaps for a time quiescent; it tries, as it were, its limbs, and proves the ground under it, and feels its way. From time to time it makes essays which fail, and are in consequence abandoned. It seems in suspense which way to go; it wavers, and at length strikes out in one definite direction. In time it enters upon strange territory; points of