António Sérgio de Sousa (September 3, 1883 – February 12, 1969) was an influential educationist, philosopher, journalist, sociologist and essayist from Portugal.
He was the only son and representative of António Sérgio de Sousa (October 22, 1842 – Lisbon, August 18, 1906) - only son and representative of the 98th Governor-General of Portuguese India, 64th Governor of Angola, 59th Governor of Macau and 1st Viscount of Sérgio de Sousa -, and second wife (m. India, Bombay, Church of Our Lady of the Glory of Mazagão, October 22, 1879) Ana Maria Henriques de Brito (Pondá, Novas Conquistas, July 23, 1855 – Lisbon, January 23, 1948).
Sérgio was an important intellectual, thinker and Portuguese politician. Born in Damão, he was influenced by the contact with different cultures. He lived many years in Africa, becoming a cosmopolitan character because, following a family tradition, he studied at the Military College, completing the course of the Navy of War, following which he travelled to Cape Verde and Macao. He left the Navy with the establishment of the Republic in 1910. Sérgio did not consider the issue republic/monarchy important. Important would be the economic progress and welfare of Portugal. He spoke about "socialism", although this was not near the "Marxist socialism". Sérgio was located in a social democratic political line, admiring England, a position similar to the one adopted by the countries of Scandinavia and their Social-Democratic Parties. Sérgio died in Lisbon.