Out of this reality came the dualistic development thesis of the international-dependence theory. Todaro and Smith advance the idea that “[i]mplicit in structural-change theories and explicit in international-dependence theories is the notion of a world of dual societies or rich nations and poor nations and, in the developing countries pockets of wealth within broad areas of poverty. Dualism is a concept widely discussed in development economics. It represents the existence and persistence of increasing divergence between rich and poor nations and rich and poor peoples on various levels