According to Osho, stupidity is a deadened absence of inquiry—one imitates the crowd, has no curiosity, and merely vegetates—whereas madness is a loss of self-awareness in which one never thinks oneself mad and believes the whole world is. The moment a mad person wonders, "Am I mad?" sanity begins. Stupidity can be helped; madness can be cured; but spiritual sleep requires self-awakening.
Stupidity doesn’t ask questions; madness can’t see itself—asking “Am I mad?” starts getting well.