of Right". He remained a sharp critic of what was to the Marxian view a destructive philosophy: This was a direct reference by Marx to Hegel's Elements of the Philosophy of Right §63 as Marx adds: Marx acknowledges that a nominal price or value can be imputed to goods or assets which are not reproducible goods and not produced by human labour, as correctly noted later by Engels that a product is not necessarily a commodity. However Marx generally holds that only human labour expended can create value compared with Nature, through instrumentation known as modus operandi, or the method of working. Transformation into a commodity "As exchange-values, all commodities are merely definite quantities of congealed labour-time", wrote Karl Marx. The discrepancy of the true purpose of value came to be one of the biggest sources of conflict between capital and labour. The transformation of a use-value into a social use-value and into a commodity (the process of commodification) is not automatic or spontaneous, but has technical, social and political preconditions. For example, it must be possible to trade it, and to transfer ownership or access rights to it from one person or organization to another in a secure way. There must also be a real market demand for it. And all that may depend greatly on the nature of the use-value itself, as well as the ability to package, store, preserve and transport it. In the case of information or communication as use-values, transforming them into commodities may be a complex and problem-fraught process. Thus, the objective characteristics of use-values are very important for understanding (1) the development and expansion of market trade, and (2) necessary technical relationships between different economic activities (e.g. supply chains). To produce a car, for example, you objectively require steel, and this steel is required, regardless of what its price might be. Necessary relationships therefore exist between different use-values, because they are technically, materially and practically related. Some authors therefore write about an "industrial complex" or "technological complex", indicating thereby how different technological products are linked in a system. A good example would be all the different products involved in the production and use of motor cars. The category of use-value is also important in distinguishing different economic sectors according to their specific type of output. Following Quesnay's analysis of economic reproduction, Marx distinguished between the economic sector producing means of production and the