No bird soars too high if he soars with his own wings.
A fool sees not the same tree that a wise man sees.
The man who never alters his opinions is like standing water, and breeds reptiles of the mind.
Without contraries is no progression. Attraction and repulsion, reason and energy, love and hate, are necessary to human existence.
I was angry with my friend: I told my wrath, my wrath did end. I was angry with my foe: I told it not, my wrath did grow.