The antithesis of wisdom is sometimes thought to be ignorance. However, this can be disproved by how there are so many well-educated and knowledgeable people who are still lacking in wisdom.
Since wisdom is often accompanied by humility, the antithesis of wisdom is sometimes thought to be confidence. However, this can be disproved by how many times truly wise people can speak with great confidence and conviction.
No, the opposite of wisdom is pride.
One can be wise and still lack certain worldly items of education or certain specific nuggets of knowledge regarding trivial details. One can be wise and display strong confidence. But it is a hallmark of wisdom that it disciplines and conquers pride.
Pride and confidence are not the same, in that confidence may exist without a dark side to it, whereas pride by its very deepest nature must carry with it aspects of an injurious outcome. Confidence by itself does not injure, in fact it may heal. Whereas proud confidence delivers an insult and wipes away any vestige of wisdom that might otherwise be a part of confident knowledge.
If one prays for and begins to receive any wisdom at all, the first likely temptation one must face will be the issue of personal pride. And it is here where too many fail their first step and are never granted any further ones from the Father. Wisdom requires humility, and pride and humility cannot exist in unison. Many a righteous man attempts to gain wisdom only to sidetrack themselves unto the path of personal pride; they become less wise and more a Pharisee the likes of which Jesus offered more than a few harsh words.