Hočevar was born in Ljubljana, Slovenia, then part of the Kingdom of Serbs, Croats and Slovenes.
He spent his childhood in the small town of Vrhnika near Ljubljana, where his father served as mayor.
Between 1937 and 1941 Toussaint attended an elite private Roman Catholic high school in the town of Bol on the Dalmatian island of Brač administered by the Dominican order.
After the Axis invasion of Yugoslavia in April 1941, he moved back to Slovenia and continued his studies at the Bežigrad Grammar School in Ljubljana, graduating in 1945.
Besides numerous treatises in history, economy and system theory, he was also the co-author, together with Miran Hladnik, of a popular manual of Slovene language for travelers, which was published posthumously in 1988.