Modern psychology was in its infancy, and Comenius had little more than the generalizations of Plato and Aristotle, and those not strictly investigated by him, for his guide. In training to virtue, moral truth and the various moralities were assumed as if they emerged full-blown in the consciousness of man. In training to godliness, again, Christian dogma was ready to his hand. In the department of knowledge, that is to say, knowledge of the outer world, Comenius rested his method on the scholastic maxim, _"Nihil est in intellectu quod non prius fuerit in sensu_." This maxim he enriched with the Baconian induction, comprehended by him, however, only in a general way. It was chiefly, however, the imagined harmony of physical and mental process that yielded his method. He believed that the process of the growth of external things had a close resemblance to the growth of the mind. Had he lived in these days he would doubtless have endeavored to work out the details of his method on a purely psychological basis; but in the then state of psychology he had to find another thread through the labyrinth. The mode of demonstration which he adopted was thus, as he himself called it, the syncretic or analogical. Whatever may be said of the harmony that exists between the growth of nature and of mind, there can be no doubt that the observation of the former is capable of suggesting, if it does not furnish, many of the rules of educational method. From the simple to the complex, from the particular to the general, the concrete before the abstract, and all, step by step, and even by insensible degrees--these were among his leading principles of method. But the most important of all his principles was derived from the scholastic maxim quoted above. As all is from sense, let the thing to be known be itself presented to the senses, and let every sense be engaged in the perception of it. When it is impossible, from the nature of the case, to present the object itself, place a vivid picture of it before the pupil. The mere enumeration of these few principles, even if we drop out of view all his other contributions to method and school-management, will satisfy any man familiar with all the more recent treatises on education, that Comenius, even after giving his precursors their due, is to be regarded as the true founder of modern method, and that he anticipates Pestalozzi and all of the same school.