Sentence:  "... A man would blush to say to himself in the darkness of the night the things he stands up on a platform in the garish light of day to stuff into the ears of a multitude whose intelligence he pretends that he esteems.... Therefore, why be <WSD>sapient</WSD> and solemn about it, like an editorial in a newspaper?" Nick added, with a smile. 
Meaning of the word marked with <WSD> tags:  Attempting to appear wise or discerning.