Collocations for stupidity - noun

complete, crass (BrE), incredible, plain, sheer, utter
It's hard to know if it's corruption or just plain stupidity by the authorities.

human

can't believe
I can't believe the stupidity of some people.

realize
I now realize the stupidity of that statement.

curse
He cursed his own stupidity.

demonstrate, show
Her answer showed the most incredible stupidity.

through (your) stupidity
Through his own stupidity, he missed an excellent opportunity.

stupidity on sb's part
It was sheer stupidity on the part of the crew.