When Karim was a high school student, Saratchandra Chatterjee's novel Pather Dabi (Demand for a Pathway) inspired him to dream of a revolution.[5] He matriculated from Barisal Zilla School in 1940.[3]
He completed his Intermediate of Arts (IA) at Dhaka Intermediate College in 1942.[3] He then became a student of Dacca University, initially studying English but soon shifting to philosophy because Haridas Bhattacharya's class lectures had attracted him.[5] He earned an honors BA, and in 1946, an MA.[6]
He left politics in 1963 and joined the translation section of the Bangla Academy.[5][6] From 1969 to 1971 he directed the academy's cultural section.[5]
In 1972, after Bangladesh won its independence, he rejoined Dacca University as a professor of political science.[6]
Karim wrote scholarly books on philosophy, among them his দর্শনকোষ (Encyclopedia of Philosophy). He has translated Plato, Aristotle, Rousseau and Engels.