I have two purposes in mind in saying this. Firstly, you must not expect too much from this science, for you cannot set contrary brains to rights by any logic. Secondly, you must not think too little of it, by regarding the matter as mere scholastic word-mongery and useless hairsplitting. In daily life, as well as in all sciences, we never operate without the help of thought, but only with it, hence an understanding of the nature of the processes of thought is of eminent value. Logic has its history like all sciences. Aristotle, whom Marx calls the "Grecian giant of thought," is universally recognized as its founder. After the classic culture of antiquity had been buried by barbarism, the name of Bacon of Verulam rose with the beginning of modern times as a philosophical light of the first order. His most famous work is entitled "Novum Organon." By the new organ he meant a new method of research which should be founded on experience, instead of the subtleties of the purely introspective method hitherto in vogue. After him, Descartes, or Cartesius, as he called himself in literature, wrote his still famous work, "About Methods." I furthermore recall Immanuel Kant's "Critique of Reason," Johann Gottlieb Fichte's "Theory of Science," and finally Hegel, of whom the biographer said that he was as famous in the scientific world as Napoleon in the political. Hegel calls his chief work "Logic," and bases his whole system on the "dialectic method." You have only to look at the titles of these philosophical masterpieces in order to recognize that they all treat of the same subject which we are making our special study, viz., the light of understanding. The great philosophers of all times have searched for the true method, the method of truth, for the way in which understanding and reason arrive at science. I merely wish to indicate that this subject has its famous history, but I do not care to enter more deeply into it. I will not speak of the oppression and persecution, which was inaugurated by religious fanaticism. I will not enumerate the various events that led to a greater and greater light from generation to generation. The attempt to trace this history would entangle us in many disputed questions and errors which would only increase the difficulties of this study for the beginner. If a teacher of technology were to instruct you on steam engines and, to explain their first incomplete invention, trace their further development historically from improvement to improvement, until he should arrive at the height of perfection attained in their present day construction, he would also be advancing on a path, but on a tedious one. I shall endeavor to show my subject at the outset in the very clearest light which has ever been thrown on it by the help of the nations of all times. If I succeed in this, it will be easy in the future, in the reading of any author, to separate the chaff from the wheat.