If you unclear about what you believe then you need to offer more choices. One of the brilliant parts of Facebook is that you can ‘like’ something or comment. There is no dislike, maybe like, perhaps, somewhat, neither buttons. You post your thoughts and friends and fans can support your sentiment or not.
Are you clear about what you believe? Perhaps one way to test this is to run a brief poll. Ask for responses. Can you accept like and dislike as the only two answers? If you need a five point scale to measure your impact, perhaps you have not been clear about your cause. One colleague put it this way, a question that requires a range of satisfaction should really say, ‘I agree and I am a fan’ and then all the other possible answers should say, ‘I do not agree but I am this polite/diplomatic.’