What’s the difference between an intelligent person, a foolish person, a stupid person, and a smart person? An intelligent person admits their mistakes and strives not to repeat them.
A foolish person realizes they’ve made a mistake but is too proud or vain to admit it, and so often ends up repeating the same mistake.
A stupid person is incapable of realizing they made a mistake, and thus can’t grasp how their actions have consequences.
A smart person figures out why they made the mistake and in doing so, learns something: Either insight into themselves, or how to make penicillin.