Antonyms for the phrase "being of the opinion" would include phrases such as "doubtful," "unsure," "ignorant," or "uncertain." These phrases indicate a lack of knowledge or certainty about a particular topic, idea, or statement. It is important to consider antonyms in order to fully understand the range of meanings and nuance behind a phrase. When we are unsure or ignorant about something, we may seek out additional information or perspectives in order to arrive at a more informed opinion. Understanding antonyms can help us navigate different contexts and interpretations of language, which is essential for effective communication and critical thinking.