The human brain performs the function of thinking as involuntarily as the chest the function of breathing. However, we can, by our will, stop breathing for a while, and accelerate or retard the breathing movements. In the same way, the will can control the thoughts. We may choose any object as the subject matter of our thought, and yet we may quickly convince ourselves that the power of our will and the freedom of the mind are not any greater than the freedom of the chest in breathing.
While logic undertakes to assign the proper position to our brain, still it has to remember that nature has already assigned that position.
It is with logic as it is with other sciences. They draw wisdom from the mysterious source of plain experience. Agriculture, e. g., aims to teach the farmer how to cultivate the soil; but fields were tilled long before any agricultural college had begun its lectures. In the same way human beings think without ever having heard of logic. But by practice they improve their innate faculty of thought, they make progress, they gradually learn to make better use of it. Finally, just as the farmer arrives at the science of agriculture, so the thinker arrives at logic, acquires a clear consciousness of his faculty of thought and a professional dexterity in applying it.
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.
I can afford to dispense with quotations and proofs from others in trying to make my case and demonstrating the positive product of social culture, for we are dealing with the most universal and omnipresent object,—one which enters into every spoken or written sentence with its own body. If anybody tells of far off times or wonderful things, he must quote witnesses. Now, much of what I have to say for my case may sound wonderful, because it runs counter to the popular prejudice, but the only witness required to prove the truth of my statements is the clear brain of my pupil, who has only to examine his own experience without preconceived notions, in order to find proofs on every hand.