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).
The extinction of plants and animals can have devastating effects on the environment as well as on humans. An EU-funded project is exploring methods to conserve biodiversity in areas where species are threatened.
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