Trade involves the transfer of goods or services from one person or entity to another, often in exchange for money. A system or network that allows trade is called a market.
The product of mental labor — science — always stands far below its value, because the labor-time necessary to reproduce it has no relation at all to the labor-time required for its original production.
Karl Marx Addenda, "Relative and Absolute Surplus Value" in Economic Manuscripts (1861–63).
Depletion and the negative environmental impact of fossil fuels are the main drivers behind the quest for renewable energy technologies. EU-funded scientists studied the potential of newly developed prototype devices to exploit geophysical flows.
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