His imagination had so wrought itself to the habit of seeing things as they probably appeared to others, that a strong partisanship, unless it were against an immediate oppression, had become an insincerity for him. 
The indefiniteness of his sentiments threatened to hinder any persistent course of action: as soon as he took up any side, he began to see things as they probably appeared to others; so that any strong partisanship, unless it were against oppression, seemed insincere to him. 