At the same time book-knowledge is indispensable, and it is essential to bring to the study of later Buddhism a scholarlike acquaintance with Sanskṛit and Pāli. Even a knowledge of Tibetan ought to be added. Nor ought the inquirer to be ignorant of the science of comparative religion, seeing that the principles of that science may throw light on many difficult questions. For example, a student of comparative religion will be prepared to expect that all religious systems will diverge more or less from their original type in the hands of enthusiastic disciples, who are ever inclined to amplify their master’s teaching and to explain it differently according to each man’s peculiar temperament and mental bias, until in the end the original deposit of simple doctrine becomes overlaid with layer upon layer of adventitious matter. Nor will he be surprised to find that the tendency of every religious movement is towards deterioration and disintegration. Nor will it appear strange to him that the chief conservative force is antagonism. As time goes on disagreements among the followers of any great leader seem to be inevitable, and always lead to sectarian divisions and subdivisions. Yet it is this opposition of religious parties that usually operates to mitigate the worst extremes of corruption, and tends to bring about re-forming movements. Even the progress of Christianity—as history shows too well—furnishes illustrations of the law of deterioration, disintegration, and re-formation. At all events, it is certain that no study of the New Testament is likely to give a true idea of the varying condition of the Christian religion as exhibited at the present day in different parts of the world. But here it is important to caution the student of religions against forcing a comparison between two systems of doctrine like Christianity and Buddhism, which are radically and essentially opposed to each other. The unchristianlike incrustations and divisions which have marred the original teaching of the Head of our religion exist _in spite_ of Christianity. They are not the result of any development of its first principles; whereas, on the contrary, the corruptions and schisms of Buddhism are the natural and inevitable outcome of its own root-ideas and fundamental doctrines. In proof of this let us revert for a moment to the insight we have gained into the origin of Buddhism.