Quite often, we become victims of our own knowledge!
Early stage of our learning, we move with doubt, caution or skeptism, depending on the topic, our previous knowledgebase, source of new information etc. However, soon the knowledge gets embedded in our very being and is taken for granted ... source & validity rarely questioned, by the self and we resist questions from others as they seem like a question on ourselves.
1+1 is assumed always to be 2, while we know that it could be different depending on the context, ... also, 1 and + are only notations for something. Till this realization comes, 1 the notation and the 1 the notion are intertwined.
Here, comes the importance of denial. In Indian approach, we say the realization (of the supreme Brahma, from the point of knowledge pursuit) can be only by denial (Ne/ethi... ie. Na Ithi ... That is "not that'). Disassociating ourselves & knowledge to its source