There are many possible answers to this question. For one thing, the council may not want the men to know the things the council discusses that are not definite. For another, they may not want the men to have knowledge so they could not rise up against them and create their own society. Or maybe they want to keep their citizens feeling inadequate and stupid by keeping them int the dark. The only thing that all these possible answers have in common is the withholding of knowledge on purpose. Because of this, I wonder how much the council really cares about it's people. Do they really want them to be happy or do they just want to have the sensation of having power over others? Or do they really believe that feeling inadequate is the best thing for these people? I do not think that this information will be reveled in the book but I think that, at least at some point, the council wanted the best for it's people and would not have withheld knowledge from it's people or created rules that would mean withholding knowledge from it's people. I think this because the council holds some good values that could not have come from cold hearted people, such as love your brothers.
Why did the council find it necessary to make the rule that if the other scholars say so a man must abandon his work?
I think that the council found this rule necessary because the scholars wanted to feel in control. A way to let the scholars feel in control without giving them power is to let them rule the men within their group. Although the council must call it a way to be equal, it must be a way to keep everybody happy and prevent an uprising.
Why do you think that the council outlawed mirrors?
I think that the council outlawed mirrors because they wanted equality between all people. If somebody knows they look different from their brothers then they may act superior. Of course, the others can still see this person so they can see if they are truly superior. But everything has it's flaws and that is not something that the all powerful council can change.