In Agassiz the theoretical and the practical life were well balanced. He was both a visionary and a man capable of bringing his visions to pass. No philosophical conception was too general for him, and no detail of observation or inference too small. No fact could appear too slight for his intense and comprehensive scrutiny, and his memory for minute resemblances and differences was vast; yet the enduring quality of his work arose from his sense of order, and from the soundness and rigor of his principles. He possessed not only physical, but intellectual and moral courage. In the face of hardship or difficulty he was undaunted, ever energetic at the moment, ever hoping for better times. His power of working was enormous, for he made virtually no false motions, but proceeded silently, swiftly, with no apparent effort, and for long periods without interruption. Much has been said by his friends of the depth and sincerity of his sentiments in point of religion. But he had little sympathy with clergymen, or with the definite forms in which the religious experience of man has expressed itself--though these forms are in their essence and development not unlike the natural forms which he so reverently studied. One who knew him well affirms that in early manhood Agassiz, if not precisely a materialist, was at all events a sceptic; but his later studies, with mature reflection, led him to believe in a Divine Creator. The external universe became to him the language in which the Divine Being conveys his ideas to man, and natural history the discipline by which men interpret that language. Thus he says, in the _Essay on Classification:_ 'To me it appears indisputable that this order and arrangement of our studies are based upon the natural, primitive relations of animal life--those systems, to which we have given the names of the great leaders of our science who first proposed them, being in truth but translations into human language of the thoughts of the Creator. And if this is indeed so, do we not find in this adaptability of the human intellect to the facts of creation, by which we become instinctively, and, as I have said, unconsciously, the translators of the thoughts of God, the most conclusive proof of our affinity with the Divine mind? And is not this intellectual and spiritual connection with the Almighty worthy of our deepest consideration? If there is any truth in the belief that man is made in the image of God, it is surely not amiss for the philosopher to endeavor, by the study of his own mental operations, to approximate the workings of the Divine Reason, learning from the nature of his own mind better to understand the Infinite Intellect from which it is derived. Such a suggestion may, at first sight, appear irreverent. But who is the truly humble? He who, penetrating into the secrets of creation, arranges them under a formula, which he proudly calls his scientific system? or he who in the same pursuit recognizes his glorious affinity