Seohak was the introduction of technology, philosophy and most prominently, Catholicism and Western ideas to Joseon Korea in the 18th century. It is also occasionally referred to as Cheonjuhak which means 'Heavenly Learning'. Literally meaning "western learning", Seohak's antonym was Donghak , or "eastern learning", which featured neo-Confucianism and other traditional ways of thought.

Seohak was the introduction of technology, philosophy and most prominently, Catholicism and Western ideas to Joseon Korea in the 18th century. It is also occasionally referred to as Cheonjuhak which means 'Heavenly Learning'. Literally meaning "western learning", Seohak's antonym was Donghak , or "eastern learning", which featured neo-Confucianism and other traditional ways of thought.