tabula rasa
From Longman Dictionary of Contemporary Englishtabula rasatab‧u‧la ra‧sa /ˌtæbjələ ˈrɑːzə/ noun [singular] literaryHBH your mind in its original state, before you have learned anythingExamples from the Corpustabula rasa• You write text, you doodle, you cross things out... quite literally a tabula rasa.• Like Raggedy Ann, she was a tabula rasa.Origin tabula rasa (1500-1600) Latin “writing board with everything cleaned off it”