What does "discernment" mean?

Discernment: The power or faculty of the mind by which it distinguishes one thing from another; power of viewing differences in objects, and their relations and tendencies; penetrative and discriminate mental vision; acuteness; sagacity; insight; as, the errors of youth often proceed from the want of discernment. -- Discernment, Penetration, Discrimination. Discernment is keenness and accuracy of mental vision; penetration is the power of seeing deeply into a subject in spite of everything that intercepts the view; discrimination is a capacity of tracing out minute distinctions and the nicest shades of thought. A discerning man is not easily misled; one of a penetrating mind sees a multitude of things which escape others; a discriminating judgment detects the slightest differences.