Dear Eugene:

In my first letter I acquainted you with my purpose, in the second I lifted the subject on my finger tips, so to say, to show it for a brief moment; in the third I showed that its color had inevitably a religious shade. Now, to continue, permit me to introduce another point to your consideration.

The great cause of the working class has hitherto always been the beast of burden of a small and exclusive minority. This is most evident in the slave states of antiquity, in Egypt, Greece, Rome. Likewise in the feudal and guild systems of the middle ages the oppression of the mass of the people is sufficiently apparent. At present this condition of things is more visible in Eastern Europe, in Russia, Turkey, Bulgaria, Hungary, Eastern Prussia, etc., than in the industrial countries of the West. In the United States of America it is most obscured, so that there the people hardly realize their enslaved condition. In America, many of the upper ten thousand have made their way from the bottom up, and it happens more frequently than in Europe that the captains of industry laid their foundation by hard work. The shortsighted observers then easily forget out of sympathy for the hard beginning that there is sharper's practice at the end, and they indulge in the idle hope that every hard working beast of burden might transform itself into a happy millionaire by thrift and smartness.

You will probably ask: What has that to do with logic or the art of reasoning? Patience! You will admit that the emancipation of the nations from beastly toil, misery and suffering is the highest goal of the human mind. Nor will you deny that the thought is the most essential instrument for reaching this high goal. The accomplishments of thought are visible in the results of civilization. The proletariat of the present, also that of Russia, Turkey, East Prussia, participates in these accomplishments of thought. It participates not alone in the sense that its brains are better educated and cultured, but also that its food, clothing, and shelter have become more civilized through the progressive deeds of intellect.

You see, then, that the people's cause is connected with the faculty of thought, and the nature of the latter may be illustrated as well by the example of the development of civilization. The complicated network of wheels in a watch may also serve to demonstrate the nature of that which language designates by many names, such as spirit, intellect, faculty of knowledge, reason, etc. Only it must be remembered that this mysterious something cannot be shown by itself, but only in connection with other things, whether they be the history of civilization or a watch. There will then be no contradiction in finding that the intellectual life appears more powerful and magnificent through the clockwork of the history of civilization than through any miniature product of thought.

In searching for the connection of things, one generally seeks to recognize the manner or the degree of the connection. But we, in this case, disregard the question as to how the things of this world are related to one another and to thought, and we simply make a note of the fact of the interdependence of thought and being, of nature and mind. This fact of the universal interconnection of things contradicts the untrained prejudice. The uncultivated brain nurses the illusion that the earth, the trees on it, and the clouds and the sun above them are separate things. But it requires a better training of reason to understand that the earth, the tree, the clouds, and the sun, can be what they are only in the universal interconnection. I remember reading an article from Fichte, in a German school reader, which clearly showed that the disarrangement of an insignificant object during the process of thinking causes us to disarrange the whole history of the world in our thoughts. It is well known that one unfamiliar with political economy overlooks the fact that the business men not only carry on their trading for their private benefit, but are also members of the process of social production. It is overlooked that all labor, aside from being individual activity, is at the same time an organic part of social labor. And just as ignorance of economics overlooks the industrial interdependence, so ignorance of logic overlooks the cosmic interrelations.

Here is a drop of water. Look how different it is according to the different things with which it is connected. It cannot be what it is without a certain temperature. According to changes in temperature, it will assume either the form of ice or of steam. In fat the drop remains compact, in salt it divides infinitely, runs downhill in general and uphill in a loaf of sugar. According to the specific gravity of a certain fluid, with which it may come into contact, it either floats on the surface or sinks. Without a connection with the earth, its temperature and gravitation, this drop and all others would disappear in the fathomless abyss and have no existence. Thus the forms of things change according to their connections, and they are what they are only as parts of the universal interrelation.

What is true of a drop of water, is true of all things, all forces and substances, even of our thoughts. The human mind lives and works only in connection with the rest of the material universe—and the recognition of the organic unity of all things is the fulcrum of my logic.

Old line metaphysical logic was so enamored of its object that the descent, the kinship, and the connection with the common things of this world seemed too ordinary for the exquisite spirit. That logic was transcendental, and therefore its chosen object likewise had to be in touch with a transcendental world. And though it was scientific enough to regard the tale of the creation of the first soul by the breath of God as a fable, it was nevertheless so prejudiced in favor of the extraordinary nature of the intellect that it did not abandon, for thousands of years, the hope of finding in that intellect a source which would reveal transcendental matters. Formal logic now entirely discards this hope of a fantastical world, but at the same time it misunderstands the natural connection between the spirit and the common world. It isolates the instrument of thought and leaves the question undecided whether this instrument has a natural, supernatural, or no connection at all. It overlooks that just as logic is real, so reality is logical, and does not see that the back door which leads to illogical heaven by way of faith deserves the disdain of science.

Thought, intellect, are really existing, and their existence is a uniform part of the universal existence. That is the cardinal point of sober logic.

The fact that the thoughts are of the same worldly substance as the other parts of the universe, that they are parts of common nature and not a transcendental essence, has already been expressed by Cartesius in the famous words: "Cogito, ergo sum," I think, therefore I am.

The fact of my thinking, says the philosopher, proves my existence. In order to come to an absolute conviction on the nature of truth and error, he sets out by doubting everything. And then he says that he cannot doubt the existence of his thoughts. He thus placed the spirit on the basis of real life, delivered it of its transcendentalism, and that constitutes his everlasting merit.

However, not alone Cartesius, but also your own experience testifies to the inseparable connection between thinking and being. Have not your thoughts been connected always and everywhere with some worldly or real object? If you attempt to isolate thought in order to ponder over it, you can only do so because that thought has been experienced by you and therefore was in every instance attached to some worldly object. True, you have thought of Greek gods, brownies, and mermaids. But you, an amateur in painting, are familiar enough with that part of the mind which is called imagination in order to admit that even this eccentric part of the mind does not only act, and therefore, exist in reality, but also derives all its products from reality, so that even its most fantastical vagaries and illusions are still real pictures, reflections of reality.

But how is it that I require such a multitude of words in order to state over and over again that the thought has a real existence and is a uniform part of the universe? Simply because from time immemorial the confusion in matters of logic is so great that the human spirit is in the same breath exalted to heaven, and yet its thoughts regarded as nothing real, nothing true. This is made plain by the fact that a sharp distinction is commonly made between that which is real and that which is only imagined, and this difference is exaggerated to such an extent that it appears as if the idea, which indeed is only in the brain, has no real existence at all.

In order that you may understand the interrelations of the things of the universe, I must warn you against this exaggeration and prove that the intellect has a real existence which is connected with the universe or reality. Botany, which occupies itself with plants, does not only teach us to divide them into classes, orders, and families, but it also does more by showing us what place in the entire realm of nature is occupied by the vegetable kingdom, by pointing out the differences which distinguish the plants from the inorganic mineral kingdom or the organic animal kingdom. Formal logic similarly dissects the spirit into its parts, makes distinctions between conceptions, ideas, judgments, conclusions, divides these into subdivisions, classifies conceptions according to species, separates abstract and concrete thought, knows many varieties of judgments, registers three, four, or more modes of conclusion. But at the same time this formal logic recoils from touching on the question as to how the universal spirit is related to the universe, what role it plays in the general existence, whether it is part and parcel of nature or transcendental. And yet this is the most interesting part, the part which logically connects the intellect and the science of the intellect with all other sciences and things.

Logic must teach us how to distinguish. It is not a question, however, of distinguishing sheet iron from gold, or a greyhound from a pug-dog, for this is done by special lines of knowledge. Logic must rather enlighten us about that part of the faculty of distinguishing which is generally required in all branches of knowledge, whereby truth and error, imagination and reality are recognized. To this end I feel impelled to advise you not to overlook that even error and imagination belong to the one infinite and absolutely coherent reality. For the purpose of distinguishing true imagination from actual reality, it must be remembered that just as rye bread and cream puffs agree in belonging to the general category of baker's products, so imagination and truth, thought and reality, are two different kinds of the same nature.

To sum up the contents of this letter, let me point out that its beginning shows the connection of the intellect with the development of the people, while its conclusion explains the wider connection of the mind with the universal existence.