Preconceived Notions

I generally prefer the phrase “preconceived notions” to “prejudice” because it doesn’t have the burden of negative connotations or even antagonism. But, the two might actually be quite different. Notions may well arise from the mid brain where the emotions and habits are lodged, while judgement, early or late, is located in the frontal lobes — i.e. the cognitive brain, which evaluates, compares and classifies information.

The reason I’m thinking about preconceived notions today is because they seem to actually interfere with perception, keeping new information from even being registered. Perhaps the emotions have a gate-keeper function? What would be the purpose? What benefit is derived from being inured to the new?