The antonyms for the phrase "thinking deeply" include a range of terms that suggest the opposite mental state. These may include concepts such as distraction, preoccupation, superficiality, lack of focus, and lack of engagement. Antonyms for thinking deeply might also include terms like mindlessness, absent-mindedness, daydreaming, or mind-wandering. All of these terms connote a mental state that is less intentional, less concentrated, and less focused on serious contemplation or problem-solving. In contrast, thinking deeply implies an active engagement with one's thoughts, an intense curiosity, and a willingness to investigate complex and provocative ideas.