Fatuousnesses refer to the state or quality of being foolish or silly. Some of the antonyms or opposite words to this term include wisdom, astuteness, prudence, sagacity, intelligence, cunningness, sharpness, and shrewdness. These words represent a high level of insight and sound judgment, which is quite the opposite of the foolishness and lack of seriousness that fatuousnesses denote. The choice of words to describe the opposite of fatuousnesses highlights the value of intelligence and good judgment. Thus, rather than engaging in foolishness or being senseless, one should aim for wisdom and intelligence in their daily decision-making, interactions, and overall lifestyle.