Mill's paradox
"The richest countries, caeteris paribus, gain the least by a given amount of foreign commerce: since, having a greater demand for commodities generally, they are likely to have a greater demand for foreign commodities, and thus modify the terms of interchange to their own disadvantage".[1]
Argentine economist José Luis Espert uses Mill's paradox to explain why openness to free market among two countries, tend to favor the smallest country.[2]