He joined the (TRIP), becoming a Commander, and was captured in North Sumatra during Operation Kraai, against the Republic of Indonesia's temporary capital in Yogyakarta (1948/49). After he was released, he graduated from high school in Medan. He studied medicine at the Nederlandsch-Indische Artsen School in Surabaya but did not graduate. He then went to the Netherlands and studied anthropology at the University of Leiden from 1954 to 1956, followed by the Full Course of the International Institute of Social Studies at The Hague, 1957; and philosophy in Paris with Prof. Jean Wahl at the Sorbonne in 1958.