noun (n)

• the mental ability to understand and discriminate between relations(noun.cognition)

  Synonym:
  discernment, judgement, judgment, sagaciousness
  

  source: wordnet30
• the trait of forming opinions by distinguishing and evaluating(noun.attribute)

  Synonym:
  judiciousness, sagaciousness
  

  source: wordnet30
• The quality of being sagacious; quickness or acuteness of sense perceptions; keenness of discernment or penetration with soundness of judgment; shrewdness.(noun)

  source: webster1913