ABSTRACT
The defenders of metaphysics have usually maintained that the human mind has the capacity of knowing certain general truths about the nature of reality by a direct insight of the reason, apart from the detailed information given by the observations of the senses. In fact, the earliest Greek philosophers loved wisdom of almost every kind, and speculated freely on a great variety of topics: mathematics, physics, biology, jurisprudence, literary criticism, was all branches of “philosophy.” The efforts of many men of outstanding genius have been devoted to it. But the result has not been the building up of a solid body of metaphysical knowledge, carrying conviction to all reasonable men. The immense variety of opinions and schools of thought to be found in the history of philosophy probably the most conspicuous and the most deeply significant division is that between the schools of materialism and idealism.
