you can't memorize everything word for word. you can't even remember the existence of all the texts you read. you just have to hope, that somewhere in the subconsciousness the thoughts with substance will stay with you. so by drawing square brackets and underlining words in books of literary fiction i am not trying to study the quotes by heart, or even remember them roughly as they are, i am trying to increase the possibility of these specific ideas becoming part of my subconscious thinking process.