Marxist authors like Arghiri Emmanuel, Charles Bettelheim, Christian Palloix, and Samir Amin showed how the distortions between the value and the prices of commodities circulating in the global economies had started a process of theft of socially necessary labor time (value transfer) from periphery to core countries, which was denominated global unequal exchange.
Amin underlined that unequal value transfers in global trade were not determined primarily by asymmetries in productivity, but by the profound wage differences between core and periphery.
[citation needed] Samir Amin used a system based on wage differences to calculate the unequal exchange with the assumptions of constant productivity and using Global Northern prices.
[10] Jason Hickel et al., using a similar method, calculated the amount that was drained from the Global South between the years 1990 to 2015 was equivalent to 242 trillion in 2010 US Dollars.
In line with Samir Amin's original suggestion, Hickel et al. used Northern prices to quantify the physical resources that were drained from the Global South in financial terms.
[12] Suwandi et al. also describe the “depeasantization of a large portion of the global periphery through the spread of agribusiness” as “central to the creation of a reserve army of unemployed.
Looking into how price inequalities are maintained, making possible the process of exploitation just outlined, Hickel et al. point to the unequal distribution of power among countries.
[19] Moreover, structural adjustments programs (SAPs) brought about massive cuts in public expenditure in the Global South, decreasing salaries, weakening labor rights and curtailing unions.
[20] Free trade agreements (FTAs) and SAPs forced global South governments to remove tariffs and subsidies and protect new industries, preventing import substitution that would have contributed to driving prices down.
Other important factors that perpetuate price inequalities are the problem of tax evasion and illicit financial flows that drive massive amounts of economic resources from Southern to Northern countries, and the structural dependence on foreign investors and access to Northern markets that forces Southern firms and countries to compete with each other, in a race to the bottom.
[21] As clearly put by Hickel et al: “Structural power imbalances in the world economy ensure that labor and resources in the South remain cheap and accessible to international capital, while Northern exports enjoy comparatively higher prices.
These price differentials enable a significant drain of labor and resources from the South.”[11] Karl Marx aimed to go beyond moral discussion, in order to establish what, objectively speaking, real values are, how they are established, and what the objective regulating principles of trade are, basing himself principally on the insights of Adam Smith and David Ricardo (but many other classical political economists as well).