In order to grasp what the concept of the "value" of a product means in Marx's work, as opposed to Marx's conception of exchange value, we must first of all examine how Marx approached the concept of "value." As is widely known, the value of a product, for example, 1 quarter of wheat, can only be expressed on the market in the form of a determined concrete product which is acquired in exchange for the first product, for example, in the form of 20 pounds of shoe polish, 2 arshins of silk, 1/2 ounce of gold, etc. Thus the "value" of the product can only appear in its "exchange value," or more precisely, in its different exchange values. However, why did not Marx confine his analysis to the exchange value of the product, and particularly to the quantitative proportions of exchange of one product for another? Why did he consider it necessary to construct the concept of value parallel with the concept of exchange value and different from it?
In the Contribution to the Critique of Political Economy, Marx did not yet sharply distinguish between exchange value and value. In the Critique, Marx began his analysis with use value, then moved to exchange value, and from there passed directly to value (which he still called Tauschwert). This transition is smooth and imperceptible in Marx's work, as if it were something obvious.
But Marx makes this transition very differently in Capital, and it is very interesting to compare the first two pages of the Critique and of Capital.
The first two pages of both works accord perfectly with each other. The exposition in both begins with use value and then passes to exchange value. The statement that exchange value is a form of quantitative interrelation or proportion in which products exchange for one another is found in both books. But after that, the two texts diverge. If in the Critique Marx passed imperceptibly from exchange value to value, in Capital he seems, on the contrary, to remain on a given point, as if foreseeing objections from his opponents. After the statement which is common to both books, Marx points out: "exchange-value appears to be something accidental and purely relative, and consequently an intrinsic value, i.e., an exchange-value that is inseparably connected with, inherent in commodities, seems a contradiction in terms. Let us consider the matter a little more closely"(C, I, p. 36).
One can see that here Marx had in mind an opponent who wanted to show that nothing exists except relative exchange values, that the concept of value is thoroughly superfluous in political economy. Who was the opponent alluded to by Marx?
This opponent was [Samuel] Bailey, who held that the concept of value is thoroughly unnecessary in political economy, that one must restrict oneself to the observation and analysis of individual proportions in which various goods are exchanged. Bailey, who was more successful in his superficiality than in his witty critique of Ricardo, tried to undermine the foundations of the labor theory of value. He maintained that it is wrong to speak of the value of a table. We can only say that the table is exchanged once for three chairs, another time for two pounds of coffee, etc.; the magnitude of the value is something thoroughly relative, and it varies in different instances. From this Bailey drew conclusions which led to the negation of the concept of value as a concept which differs from the relative value of a given product in a given act of exchange. Let us imagine the following case: the value of a table equals three chairs. A year later, the table is exchanged for six chairs. We think we are right if we say that even though the exchange value of the table has changed, its value has remained unchanged. Only the value of the chairs fell, to half their former value. Bailey finds this statement meaningless. Since the relation of exchange between the table and the chairs changed, the relation of the chairs to the table changed also, and the value of the table consists only of this.
In order to disprove Bailey's theory, Marx considered it necessary to develop (in Capital) the conception that exchange value cannot be grasped if it is not reduced to some common factor, namely to value. The first section of Chapter 1 of Capital is devoted to giving a foundation to this idea of the transition from exchange value to value and from value to the common basis under both, namely labor. Section 2 is a completion of Section 1, since here the concept of labor is analyzed in greater detail. We may say that Marx passed from the differences which are manifested in the sphere of exchange value to the common factor which is at the basis of all exchange values, namely to value (and in the last analysis, to labor). Here Marx shows the inaccuracy of Bailey's conception of the possibility of restricting analysis to the analysis of the sphere of exchange value. In Section 3, Marx undertakes the opposite course and explains the way the value of a given product is expressed in its various exchange values. Earlier Marx had been led by analysis to the common factor, and now he moves from the common factor to the differences. Earlier he refuted Bailey's conception, and now he completes Ricardo's theory, which did not explain the transition from value to exchange value. In order to refute Bailey's theory, Marx had to develop Ricardo's theory further.
Actually, Bailey's attempt to show that there is no value other than exchange value, was facilitated significantly by Ricardo's onesidedness. Ricardo could not show how value is expressed in a determined form of value. Thus Marx had two tasks: 1) he had to show that value must be revealed behind exchange value; 2) he had to prove that the analysis of value necessarily leads to different forms of its manifestation, to exchange value.
How did Marx make the transition from exchange value to value?
Usually, critics and commentators of Marx hold that his central argument consists of his famous comparison of wheat and iron on page 3 of the first volume of the German edition of Capital. If wheat and iron are equated with each other, Marx reasoned, then there must be something common to both and equal in magnitude. They must be equal to a third thing, and this is precisely their value. One usually holds that this is Marx's main argument. Almost all critiques of Marx's theory are directed against this argument. Unfortunately, every work directed against Marx maintains that Marx tried to prove the necessity of the concept of value by means of purely abstract reasoning.
But what has been completely overlooked is the following circumstance. The paragraph in which Marx treats the equality of the wheat and the iron is merely a deduction from the previous paragraph, which says: "A given commodity, e.g., a quarter of wheat is exchanged for x blacking, y silk, or z gold, &c. - in short, for other commodities in the most different proportions. Instead of one exchange-value, the wheat has, therefore, a great many. But since x blacking, y silk, or z gold, &c., each represent the exchange-value of one quarter of wheat, x blacking, y silk, z gold, &c., must, as exchange-values, be replaceable by each other, or equal to each other. Therefore, first: the valid exchange-values of a given commodity express something equal; secondly, exchange-value, generally, is only the mode of expression, the phenomenal form, of something contained in it, yet distinguishable from it" (C, I, p. 37).
As can be seen from this passage, Marx does not examine the individual case of equalization of one commodity for another. The starting-point of the argument is a statement of a well-known fact about the commodity economy, the fact that all commodities can be equalized with each other, and the fact that a given commodity can be equated with an infinity of other commodities. In other words, the starting point of all of Marx's reasoning is the concrete structure of the commodity economy, and not the purely logical method of comparison of two commodities with each other.
Thus Marx starts from the fact of manyfold equalization of all commodities with each other, or from the fact that every commodity can be equated with many other commodities. However, this premise in itself is still not enough for all the conclusions which Marx reached. At the basis of these conclusions there is still a tacit assumption which Marx formulates in various other places.
Another premise consists of the following: we assume that the exchange of one quarter of wheat for any other commodity is subsumed by some regularity. The regularity of these acts of exchange is due to their dependence on the process of production. We reject the premise that the quarter of wheat can be exchanged for an arbitrary quantity of iron, coffee, etc. We cannot agree with the premise that the proportions of exchange are established every time, in the act of exchange itself, and thus have a completely accidental character. On the contrary, we affirm that all the possibilities for the exchange of a given commodity for any other commodity are subsumed under certain regularities based on the production process. In such a case, Marx's entire argument takes the following form.
Marx says: Let us take, not the chance exchange of two commodities, iron and wheat, but let us take exchange in the form in which it actually takes place in a commodity economy. Then we will see that every object can be equalized with all other objects. In other words, we see an infinity of proportions of exchange of the given product with all others. But these proportions of exchange are not accidental; they are regular, and their regularity is determined by causes which lie in the production process. Thus we reach the conclusion that the value of a quarter of wheat is expressed once in two pounds of coffee, another time in three chairs, and so on, independently of the fact that the value of a quarter of wheat has remained the same in all these cases. If we assumed that in each of the infinite proportions of exchange, the quarter of wheat has another value (and this is what Bailey's statement can be reduced to), then we would admit complete chaos in the phenomenon of price formation, in the grandiose phenomenon of the exchange of products by means of which the comprehensive interrelation of all forms of labor is carried out.
The above reasoning led Marx to the conclusion that even though the value of the product is necessarily manifested in exchange value, he would have to subsume the analysis of value under that of exchange value and independently of it. "The progress of our investigation will show that exchange-value is the only form in which the value of commodities can manifest itself or be expressed. For the present, however, we have to consider the nature of value independently of this, its form" (C., I, p. 38). Consistently with this, in the first and second sections of Chapter 1 of Capital, Marx analyzed the concept of value in order to pass to exchange value. This distinction between value and exchange value leads us to ask: what is value as opposed to exchange value.
If we take the most popular and most widely held view, then, unfortunately, we can say that value is usually considered to be the labor which is necessary for the production of given commodities. However, the exchange value of given commodities is seen as another product for which the first commodity is exchanged. If a given table is produced in three hours of labor and is exchanged for three chairs, one usually says that the value of the table, equal to three hours of labor, was expressed in another product different from the table itself, namely in three chairs. The three chairs make up the exchange value of the table.
This popular definition usually leaves unclear whether the value is determined by the labor or whether the value is the labor itself. Obviously, from the point of view of Marx's theory, it is accurate to say that exchange value is determined by labor, but then we must ask: what is the value determined by labor, and to this question we usually do not find an adequate answer in the popular explanations.
This is why the reader frequently forms the idea that the value of the product is nothing other than the labor necessary for its production. One gets a false impression of the complete identity between labor and value.
Such a conception is very widespread in anti-Marxist literature. One may say that a large number of the misunderstandings and misinterpretations which can be found in anti-Marxist literature are based on the false impression that, according to Marx, labor is value.
This false impression often grows out of the inability to grasp the terminology and meaning of Marx's work. For example, Marx's well-known statement that value is "congealed" or "crystallized" labor is usually interpreted to mean that labor is value. This erroneous impression is also created by the double meaning of the Russian verb "represent" (predstavlyat'). Value "represents" labor - this is how we translate the German verb "darstellen." But this Russian sentence can be understood, not only in the sense that value is a representation, or expression, of labor - the only sense which is consistent with Marx's theory - but also in the sense that value is labor. Such an impression, which is the most widespread in critical literaturedirected against Marx, is of course completely false. Labor cannot be identified with value. Labor is only the substance of value, and in order to obtain value in the full sense of the word, labor as the substance of value must be treated in its inseparable connection with the social "value form" (Wertform).
Marx analyzes value in terms of its form, substance and magnitude (Wertform, Wertsubstanz, Wertgrosse). "The decisive, crucial point consists of revealing the necessary internal connection between the form, substance and magnitude of value" (Kapital, 1, 1867, p. 34). The connection between these three aspects was hidden from the eyes of the analyst because Marx analyzed them separately from each other. In the first German edition of Capital, Marx pointed out several times that the subject was the analysis of various aspects of one and the same object: value. "Now we know the substance of value. It is labor. We know the measure of its magnitude. It is labor-time. What still remains is its form, which transforms value into exchange value" (Ibid., p. 6; Marx's italics). "Up to now we have defined only the substance and magnitude of value. Now we turn to the analysis of the form of value" (Ibid., p. 13). In the second edition of Volume I of Capital, these sentences were excluded, but the first chapter is divided into sections with separate headings: the heading of the first section says, "Substance of Value and Magnitude of Value"; the third section is titled: "Form of Value or Exchange Value." As for the second section, which is devoted to the two-fold character of labor, it is only a supplement to the first section, i.e., to the theory of the substance of value.
Leaving aside here the quantitative aspect, or the magnitude of value, and limiting ourselves to the qualitative aspect, we can say that value has to be considered in terms of "substance" (content) and "form of value."  The obligation to analyze value in terms of both of the factors included within it means an obligation to keep to a genetic (dialectic) method in the analysis. This method contains analysis as well as synthesis.  On one hand, Marx takes as his starting-point the analysis of value as the finished form of the product of labor, and by means of analysis he uncovers the content (substance) which is contained in the given form, i.e., labor. Here Marx follows the road which was paved by the Classical Economists, particularly Ricardo, and which Bailey refused to follow. But on the other hand, because Ricardo had confined himself to the reduction of form (value) to content (labor) in his analysis, Marx wants to show why this content acquires a given social form. Marx does not only move from form to content, but also from content to form. He makes the "form of value" the subject of his examination, namely value as the social form of the product of labor - the form which the Classical Economists took for granted and thus did not have to explain.
Reproaching Bailey for limiting his analysis to the quantitative aspect of exchange value and for ignoring value, Marx observes that the classical school, on the other hand, ignored the "form of value" even though it subjected value itself (namely the content of value, its dependence on labor) to analysis. "Political Economy has indeed analyzed, however incompletely, value and its magnitude, and has discovered what lies beneath these forms. But it has never once asked the question why labor is represented by the value of its product and labor-time by the magnitude of that value" (C., I, p. 80). The Classical Economists uncovered labor under value; Marx showed that the working relations among people and social labor necessarily take the material form of the value of products of labor in a commodity economy. The classics pointed to the content of value, to labor expended in the production of the product. Marx studied above all the "form of value," i.e., value as the material expression of the working relations among people and social (abstract) labor. 
"The form of value" plays an important role in Marx's theory of value. However, it did not attract the attention of critics (except Hilferding).  Marx himself mentions "the form of value" in variouspassages incidentally. The third section of Chapter I of Capital has the title "Form of Value or Exchange Value." But Marx does not remain on the explanation of the form of value, and quickly passes to its various modifications, to the individual "forms of value": accidental, expanded, general and monetary. These different "forms of value," which are included in every popular presentation of Marx's theory, overshadowed the "form of value" as such. Marx elaborated the "form of value" in greater detail in the passage mentioned above: "It is one of the chief failings of classical economy that it has never succeeded, by means of its analysis of commodities, and in particular, of their value, in discovering that form under which value becomes exchange-value. Even Adam Smith and Ricardo, the best representatives of the school, treat the form of value as a thing of no importance, as having no connection with the inherent nature of commodities. The reason for this is not solely because their attention is entirely absorbed in the analysis of the magnitude of value. It lies deeper. The value-form of the product of labor is not only the most abstract, but is also the most universal form, taken by the product in bourgeois production, and stamps that production as a particular species of social production, and thereby gives it its special historical character. If then we treat this mode of production as one eternally fixed by Nature for every state of society, we necessarily overlook that which is the differentia specifica of the value-form, and consequently of the commodity-form, and of its further developments, money-form, capital-form, &c." (C., I, pp. 80-81, footnote. Rubin's italics).
Thus the "value form" is the most general form of the commodity economy; it is characteristic of the social form which is acquired by the process of production at a determined level of historical development. Since political economy analyzes a historically transient social form of production, commodity capitalist production, the "form of value" is one of the foundation stones of Marx's theory of value. As can be seen from the sentences quoted above, the "form of value" is closely related to the "commodity form," i.e., to the basic characteristic of the contemporary economy, the fact that the products of labor are produced by autonomous, private producers. Aworking connection between producers is brought about only by means of the exchange of commodities. In such a "commodity" form of economy, social labor necessary for the production of a given product is not expressed directly in working units, but indirectly, in the "form of value," in the form of other products which are exchanged for the given product. The product of labor is transformed into a commodity; it has use value and the social "form of value." Thus social labor is "reified," it acquires the "form of value," i.e., the form of a property attached to things and which seems to belong to the things themselves. This "reified" labor (and not social labor as such) is precisely what represents value. This is what we have in mind when we say that value already includes within itself the social "form of value."
However, what is that "form of value" which, as opposed to exchange value, is included in the concept of value?
I will mention only one of the dearest definitions of the form of value in the first edition of Capital: "The social form of commodities and the form of value (Wertform), or form of exchangeability (form der Austauschbarkeit) are, thus, one and the same (Kapital, 1, 1867, p. 28; Marx's italics). As we can see, the form of value is called a form of exchangeability, or a social form of the product of labor which resides in the fact that it can be exchanged for any other commodity, if this exchangeability is determined by the quantity of labor necessary for the production of the given commodity. In this way, when we have passed from exchange value to value, we have not abstracted from the social form of the product of labor. We have abstracted only from the concrete product in which the value of the commodity is expressed, but we still have in mind the social form of the product of labor, its capacity to be exchanged in a determined proportion for any other product.
Our conclusion can be formulated in the following way: Marx analyzes the "form of value" (Wertform) separately from exchange value (Tauschwert). In order to include the social form of the product of labor in the concept of value, we had to split the social form of the product into two forms: Wertform and Tauschwert. By the first we mean the social form of the product which is not yet concretized in determined things, but represents some abstract property of commodities. In order to include in the concept of value the properties of the social form of the product of labor and thus show the inadmissibility of identifying the concept of value with the concept of labor, an identification which was often approached by popular presentations of Marx, we have to prove that value must be examined not only from the aspect of the substance of value (i.e.,labor), but from the aspect of the "form of value." In order to include the form of value in the concept of value itself, we have to separate it from exchange value, which is treated separately from value by Marx. Thus we have broken down the social form of the product into two parts: the social form which has not yet acquired a concrete form (i.e., "form of value"), and the form which already has a concrete and independent form (i.e., exchange value).
After we have examined the "form of value," we must pass on to the examination of the content or substance of value. All Marxists agree that labor is the content of value. But the problem is, what kind of labor is under consideration. It is known to us that the most different forms may be hidden under the word "labor." Precisely what kind of labor makes up the content of value?
After having drawn a distinction between socially equalized labor in general, which can exist in different forms of social division of labor, and abstract labor, which exists only in a commodity economy, we must ask the following question: does Marx understand, by substance or content of value, socially equalized labor in general (i.e., social labor in general), or rather abstractly universal labor? In other words, when we speak of labor as the content of value, do we include in the concept of labor all those characteristics which were included in the concept of abstract labor, or do we take labor in the sense of socially equalized labor, not including in it those properties which characterize the social organization of labor in the commodity economy? Does the concept of labor as the "content" of value coincide with the concept of "abstract" labor which creates value? At first glance, one can find in Marx's work arguments in favor of both of these meanings of the content of value. We can find arguments which seem to hold that labor as the content of value is something poorer than abstract labor, i.e., labor without those social propertieswhich belong to it in a commodity economy.
What arguments do we find in favor of this solution?
By content of value, Marx often referred to something which may acquire the social form of value but can also take on another social form. By content is understood something which can take various social forms. Socially equalized labor has precisely this capacity, but not abstract labor (i.e., labor which has already acquired a determined social form). Socially equalized labor may take on theform of labor organized in a commodity economy and the form of labor organized, for example, in a socialist economy. In other words, in a given case we take the social equalization of labor abstractly, not paying attention to the modifications which are called forth in the content (i.e., labor) by one or the other of its forms.
Can one find the concept of content of value in this sense in Marx's work? We can answer this question affirmatively. We remember, for example, in Marx's words, that "exchange-value is a definite social manner of expressing the amount of labor bestowed upon an object" (C., I, p. 82). It is obvious that labor is here treated as the abstract content which can take this or that social form. When Marx, in the well-known letter to Kugelmann of July 11, 1868, says that the social division of labor is manifested in the commodity economy in the form of value, he again treats socially allocated labor as the content which can take this or that social form. In the second paragraph of the section on Commodity Fetishism, Marx says directly that "the content of the determination of value" can be found not only in the commodity economy but also in the patriarchal family or on the feudal estate. Here, too, as we can see, labor is treated as the content which can take various social forms.
However, in Marx's work one can also find arguments in favor of the opposite viewpoint, according to which we must consider abstract labor as the content of value. First of all, we find in Marx's work some statements which directly say this, for example the following: "They (commodities) are related to abstract human labor as to their general social substance" (Kapital, 1, 1867, p. 28. Italics by I. R.). This statement seems to leave no doubt about the fact that abstract labor is not only the creator of value, but also the substance and content of value. We reach this same conclusion on the basis of methodological considerations. Socially equalized labor acquires the form of abstract labor in the commodity economy, and only from this abstract labor follows the necessity of value as the social form of the product of labor. From this it follows that the concept of abstract labor in our schema directly precedes the concept of value. One might say that this concept of abstract labor must be taken as the basis, as the content and substance of value. One cannot forget that, on the question of the relation between content and form, Marx took the standpoint of Hegel, and not of Kant. Kant treated form as something external in relation to the content, and as something which adheres to the content from the outside. From the standpoint of Hegel's philosophy, the content is not in itself something to which form adheres from the outside. Rather, through its development, the content itself gives birth to the form which was already latent in the content. Form necessarily grows out of the content itself. This is a basic premise of Hegel's and Marx's methodology, a premise which is opposed to Kant's methodology. From this point of view, the form of value necessarily grows out of the substance of value. Therefore, we must take abstract labor in all the variety of its social properties characteristic for a commodity economy, as the substance of value. And, finally, if we take abstract labor as the content of value, we achieve a significant simplification of Marx's entire schema. In this case, labor as the content of value does not differ from labor which creates value.
We have reached the paradoxical position that Marx sometimes takes social (or socially equalized) labor, and sometimes abstract labor, as the content of value.
How can we get out of this contradiction? The contradiction disappears if we remember that the dialectical method includes both methods of analysis which we treated above: the method of analysis from form to content, and the method from content to form. If we start from value as a determined, previously given social form, and if we ask what is the content of this form, then it is clear that this form only expresses, in general, the fact that social labor is expended. Value is seen as a form which expresses the fact of social equalization of labor, a fact which does not only take place in a commodity economy but can take place in other economies. Passing analytically from finished forms to their content, we find socially equalized labor as the content of value. But we will reach another conclusion if we take as our starting point, not the finished form, but the content itself (i.e., labor), from which the form necessarily follows (i.e., value). In order to pass from labor, considered as the content, to value as the form, we must include the concept of labor in the social form which belongs to it in the commodity economy, i.e., we must now recognize abstractly universal labor as the content of value. It is possible that the seeming contradiction in the determination of the content of value which we find in Marx's work can be explained precisely in terms of the difference between the two methods.
Since we have separately analyzed the form and the content of value, we must treat the relation between them. What relation exists between labor and value? The general answer to this question is: value is the adequate and exact form for expressing the content of value (i.e., labor). In order to clarify this idea, we return to the previous example: the table is exchanged for three chairs. We say that this process of exchange is determined by a certain regularity and depends on the development and changes in productivity of labor. But exchange value is the social form of the product of labor which not only expresses the changes of labor, but which also masks and hides these changes. It hides them because of the simple reason that exchange value presupposes a value relation between two commodities - between the table and the chairs. Thus changes in the exchange proportion between these two objects do not tell us whether the quantity of labor expended on the production of the table or the quantity of labor expended on the production of the chairs has changed. If the table, after a certain time, is exchanged for six chairs, the exchange value of the table has changed. However, the value of the table itself may not have changed at all. In order to analyze, in pure form, the dependence of the change of the social form of the product on the quantity of labor expended on its production, Marx had to divide the given event into two parts, to split it, and to say that we must analyze separately the causes which determine the "absolute" value of the table and the causes which determine the "absolute" value of the chairs; and that one and the same act of exchange (namely the fact that the table now exchanges for six chairs instead of three) may be brought about either by causes which act on the table, or by causes whose roots lie in the production of the chairs. To treat separately the effect of each of these causal chains, Marx had to split the changes of exchange value of the table into two parts, and to assume that these changes were brought about by causes which lay exclusively in the table, i.e., changes in the productivity of labor necessary for the production of the table. In other words, he had to assume that the chairs as well as all other commodities for which our table would exchange, maintain their previous value. Only with this assumption is value a completely accurate and adequate form for expressing labor in its qualitative and quantitative aspects.
Until now we have examined the connection between the substance and the form of value from its qualitative aspect. Now we must examine this same connection from its quantitative aspect. Thus we pass from the substance and form to the third aspect of value, the magnitude of value. Marx treats social labor not only from its qualitative aspect (labor as the substance of value), but from the quantitative as well (amount of labor). In the same way, Marx examines value from the qualitative aspect (as form, or form of value), and from the quantitative aspect (magnitude of value). From the qualitative aspect, the interrelations between the "substance" and "form of value" signify interrelations between socially abstract labor and its "reified" form? i.e., value. Here Marx's theory of value directly approaches his theory of commodity fetishism. From the quantitative aspect, we are concerned with the interrelations between the quantity of abstract, socially necessary labor and the magnitude of the value of the product, whose change is the basis for the regular movement of market prices. The magnitude of value changes in dependence on the quantity of abstract, socially-necessary labor, but because of the twofold character of labor the changes in the quantity of abstract, socially-necessary labor are caused by changes in the quantity of concrete labor, i.e., by the development of the material-technical process of production, in particular the productivity of labor. Thus, the entire system of value is based on a grandiose system of spontaneous social accounting and comparison of the products of labor of various types and performed by different individuals as parts of the total social abstract labor. This system is hidden and cannot be seen on the surface of events. In turn, this system of total social abstract labor is put into motion by the development of material productive forces which are the ultimate factor of development of society in general. Thus Marx's theory of value is connected with his theory of historical materialism.
In Marx's theory we find a magnificent synthesis of the content and form of value on the one hand, and the qualitative and quantitative aspects of value on the other. In one passage Marx points out that Petty confused two definitions of value: "value as the form of social labor" and "the magnitude of value which is determined by equal labor time, according to which labor is treated as the source of value" (Theorien uber den Mehrwert, V. I, 1905, p. 11). Marx's greatness lies precisely in the fact that he gave a synthesis of both of these definitions of value. "Value as the material expression of the production relations among people," and "value as a magnitude determined by the quantity of labor or labor-time" - both of these definitions are inseparably connected in Marx's work. The quantitative aspect of the concept of value, on the analysis of which the classical economists predominantly concentrated, is examined by Marx on the basis of analysis of the qualitative aspect of value. It is precisely the theory of the form of value or of "value as the form of social labor" which represents the most specific part of Marx's theory of value as opposed to the theory of the classical economists. Among bourgeois scientists, one can frequently find the idea that the characteristic feature of Marx's work in comparison with the classical economists consists of his recognition of labor as the "source" or "substance" of value. As can be seen from the passages by Marx which we cited, the recognition of labor as the source of value can also be found among economists who are mainly interested in the quantitative phenomena related to value. In particular, the recognition of labor as the source of value can also be found in Smith and Ricardo. But we would look in vain to these writers for a theory of "value as the form of social labor."
Before Marx, the attention of the classical economists and their epigones was drawn either to the content of value, mainly its quantitative aspect (amount of labor), or to relative exchange value, i.e., to the quantitative proportions of exchange. Two extreme ends of the theory of value were subjected to analysis: the fact of development of productivity of labor and technique as the internal cause of changes of value, and the fact of relative changes of value of commodities on the market. But the direct connection was missing: the "form of value", i.e., value as the form which is characterized by the reification of production relations and the transformation of social labor into a property of the products of labor. This explains Marx's reproaches of his predecessors, which one might at first glance say are contradictory. He reproaches Bailey for examining the proportions of exchange, i.e., exchange value, ignoring value. He sees the shortcoming of the classics in the fact that they examined value and the magnitude of value, the content, and not the "form of value." Marx's predecessors, as was pointed out, paid attention to the content of value mainly from the quantitative aspect (labor and the magnitude of labor), and in the same way, the quantitative aspect of exchange value. They neglected the qualitative aspect of labor and value, the characteristic property of the commodity economy. Analysis of the "form of value" is precisely what gives a sociological character and specific traits to the concept of value. This "form of value" brings together the ends of the chain: the development of productivity of labor, and market phenomena. Without the form of value, these ends separate and each of them is transformed into a one-sided theory. We acquire labor expenditures from the technical side, independent from the social form of the material process of production (labor value as the logical category), and relative changes of prices on the market, a theory of prices which seeks to explain the fluctuations of prices outside of the sphere of the labor process and cut off from the basic fact of the social economy, from the development of productive forces.
Showing that without the form of value there is no value, Marx acutely grasped that this social form, without the labor content which fills it, remains empty. Noticing the neglect of the form of value on the part of the classical economists, Marx warns us of another danger, namely of overestimating the social value-form at the expense of its labor-content. "This led to the rise of a restored mercantile system (Ganilh, &c.), which sees in value nothing but a social form, or rather the unsubstantial ghost of that form"(C., I, p. 81, footnote.) 
In another place Marx said of the same Ganilh:
"Ganilh is quite right when he says of Ricardo and most economists that they consider labor without exchange, although their system, like the whole bourgeois system, rests on exchange value." 
Ganilh is right when he emphasizes the meaning of exchange, i.e., the determined social form of working activity among people which is expressed in the "form of value." But he exaggerates the meaning of exchange at the expense of the productive-labor process: "Ganilh imagines, with the Mercantilists, that the magnitude of value is itself the product of exchange, whereas in fact it is only the form of value or the form of commodity which the product receives through exchange." 
The form of value is supplemented by the labor content, the magnitude of value depends on the amount of abstract labor. In its turn labor, which is closely connected with the system of value by its social or abstract aspect, is closely related to the system of material production by its material-technical, or concrete, aspect.
As a result of the analysis of value from the aspect of its content (i.e., labor) and its social form, we acquire the following advantages. We straight away break with the widespread identification of value and labor and thus we define the relationship of the concept of value to the concept of labor more accurately. We also define the relation between value and exchange value more accurately. Earlier, when value was treated simply as labor and was not given distinct social characteristics, value was equated with labor on one hand, and was separated from exchange value by an abyss on the other hand. In the concept of value economists frequently duplicated the same labor. From this concept of value they could not move to the concept of exchange value. Now when we consider value in terms of content and form, we relate value with the concept which precedes it, abstract labor (and in the last analysis with the material process of production), the content. On the other hand, through the form of value we have already connected value with the concept which follows it, exchange value. In fact, once we have determined that value does not represent labor in general, but labor which has the "form of exchangeability" of a product, then we must pass from value directly to exchange value. In this way, the concept of value is seen to be inseparable from the concept of labor on one hand, and from the concept of exchange value on the other.
Here and later, "form of value" (Wertform) does not mean the various forms which value acquired in its development (for example, accidental, expanded, and general forms of value), but of value itself, which is considered as the social form of the product of labor. In other words, here we do not have in mind the various "forms of value," but "value as form."
On these methods, see above, the end of Chapter Four.
We leave aside the controversial question of whether or not Marx interpreted the Classics correctly. We suppose that in relation to Ricardo, Marx was right when he said that Ricardo examined the quantity and partially the content of value, ignoring the form of value (See Theorien uber den Mehwert, Vol. II, Book I, p. 12 and Vol. III, p. 163, 164). For more detailed analysis, see our article, "Basic Characteristics of Marx's Theory of Value and Its Difference from Ricardo's Theory," included in Rozenberg, Teoriya stoimosti u Rikardo i Marksa (Theory of Value in Ricardo and Marx), Moskva: Moskovskii Rabochii, 1924.
The significance of the form of value for an understanding of Marx's theory was noticed by S. Bulgakov in his old and interesting articles ("Chto takoye trudovaya tsennost" [What is Labor Value] in Sbornike pravovedeniya i obshcheslvennykh znanii [Essays on Jurisprudence and Social Science], 1896, V, VI, p. 234, and "O nekotorykh osnovnykh ponyatiyakh politicheskoi ekonimii" [On Some Basic Concepts of Political Economy] in Nauchnom Obozrenii [Scientific Survey], 1898, No. 2, p. 337.
 In the German original, Marx simply says: substanzlosen Schein (p. 47). Translators who did not pay adequate attention to the distinction between theform and the content (substance) felt it necessary to include the word "independent," which Marx did not include. Struve translates substanzlosen with the words "without content," which accurately translates Marx's concept, which saw in the "substance" of value its content, as opposed to its form.
 Theories of Surplus Value, Moscow: Foreign Languages Publishing House, 1956, Part I, p. 199.
Ibid., p. 200.