stupidity:
intelligence,
acumen,
sense,
Canniness,
wisdom,
shrewdness,
judgment.
noun:
insight,
Sageness,
reasonableness,
rationality,
cleverness,
prudence,
perspicacity,
sagaciousness,
brightness,
logicalness,
perception,
sensibleness,
astuteness,
brilliance,
rationalness,
sharpness,
sagacity,
quickness,
discernment,
sapience,
keenness,
soundness,
sanity,
reasonability,
validity,
wit,
quick-wittedness,
logicality,
braininess,
alertness,
Percipience,
judgment,
smartness.