愚昧 is read as ぐまい (gumai) and means stupid.
ぐまい
gumai
むちぐまい
unenlightened
ぼんようぐまい
ordinary and ignorant
ぐち
moha (ignorance, folly)
おろか
foolish
ぐれんたい
gang of young toughs
ぐ
I
ぐこう
foolish act
ぐちょく
simple honesty
ぐろう
mockery
ぐみんせいさく
policy of keeping the people ignorant and easily subjugated
ぐこうやまをうつす
where there's a will, there's a way
ぐもんぐとう
silly questions and silly answers