Joseph Dietzgen

"The materialist theory of knowledge amounts, then, to this statement, that the human organ of cognition radiates no metaphysical light, but is a piece of Nature which pictures other pieces of Nature whose essence is explained when we describe it and bring it in connection with the whole Universe as the one Reality and the real Unity. Such a description demands from the epistemologist or philosopher that he should treat his subject in the same precise way as the animal world is treated by the zoologist. Should I be reproached with not following this precept immediately, I would point to Rome which, too, was not built in one day."

"One who knows little may explain that little with more ease and efficacy than one who has his head stuffed full of the prescribed bunch of official wisdom."

"Nothing can be learned without mental exertion. If you are concerned in your further development, you will recognize the Christian word as to the curse of work as untrue. Work cannot be descended from sin, for it is a blessing. You will have experienced in yourself how elated one feels after successful physical or mental work."

"My logic deserves its proletarian qualification for the reason that it requires for its understanding the overcoming of all prejudices by which the capitalist world is held together."

"Logic aims to instruct the human mind as to its own nature and processes; it will lay bare the interior working of our mind for our guidance. The object of the study of logic is thought, its nature, and its proper classification."

"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."

"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."

"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."

"It is a peculiarity of thought that it never stays with itself, but always digresses to other things."

"But it is not alone the harmony of music which has such a power over the mind. The harmony of colors, every art and science, has the same power. Even the most common craft, and the most prosaic of all prose, the chase after the dollar, may take possession of a man’s soul and prostrate him in adoration before its idol."

"Anything which may take possession of one’s soul shares its sublimity with all other things, and is for this reason at the same time something ordinary. Without such a dialectic clarification of our consciousness all adoration is idol worship."

"Adherents of formal logic may be compared to a maker of porcelain dishes who would contend that he was simply paying attention to the form of his dishes, pots, and vases, but that he did not have anything to do with the raw material."

"Such is the importance of Dietzgen—a worker who arrived at dialectical materialism, i.e., Marx’s philosophy, independently."