perspicacity

noun

Skill in perceiving, discriminating, or judging: acumen, astuteness, clear-sightedness, discernment, discrimination, eye, keenness, nose, penetration, perceptiveness, percipience, percipiency, sagacity, sageness, shrewdness, wit. See ability/inability, careful/careless.

The noun has 2 meanings:

Meaning #1: intelligence manifested by being astute (as in business dealings)
  Synonyms: shrewdness, astuteness, perspicaciousness

Meaning #2: the capacity to assess situations or circumstances shrewdly and to draw sound conclusions
  Synonyms: judgment, judgement, sound judgment, sound judgement