At the beginning of this century Western scholars put forth the concept of "social cost." They feel that in economic activity the price manufacturers and consumers must pay is not just "internal (private) cost" but also "external cost." Only by taking the two into consideration can the true cost be reflected.
西方學者在本世紀初提出「社會成本」的觀念，認為在經濟活動中，生產者與消費者所應支付的不該只是「內部（私人）成本」，應該再加上「外部成本」，才能真正反映所有的成本。