With its origin in Greek where "diaspora" as a noun means "a dispersion" or as a verb means to "scatter about", the term is used in this paper to refer to the dispersion or scattering of Africans from their original African homeland and now live in countries other than their own. Indeed some Africans have dispersed from their own countries to other countries in Africa. For the purposes of this paper our analysis focuses on Africans who live outside Africa. This paper explores the African diaspora phenomenon starting from the commercial extraction of Africans as resources to serve as inputs into plantain development in North America and manual labourers in Europe, South America and the Caribbean, to the colonial exploitation of African peoples during the "Scramble for Africa", to political exiles and economic refugees that ensued, following political independence and instabilities, and to expert skilled migrations of Africans abroad, including digital diaspora. Grounded in the educational philosophy of human and social capital theory, the paper presents a cost benefit analysis of the gains and losses that Africans and African countries have experienced as a result of the African diaspora phenomenon. The analysis leads to the philosophical conclusion that whereas the initial dispersion of Africans to overseas countries represented a significant cost to the human and social capital of Africa, African diaspora in the 21st century have potential to improve the human and social capital not only for themselves and their former homeland, but also in the host countries.