There are several antonyms for the adverb "bullheadedly," which refers to acting stubbornly, without regard for reason or advice. These antonyms include "flexibly," "adaptably," "cooperatively," "open-mindedly," "thoughtfully," "cautiously," and "deliberately." Flexibly means being able to change plans or decisions easily, based on new information or circumstances. Adaptably indicates being willing to adjust to new situations, challenges or expectations. Cooperatively means working collaboratively with others, listening to their ideas, and incorporating them into problem-solving efforts. Open-mindedly suggests being curious, receptive to new ideas, and willing to consider a variety of viewpoints. Thoughtfully refers to acting with careful consideration, reflection, and foresight.