If they are reluctant, then it will be very difficult to convince them of anything because their mind is closed to your concept. For instance, a group of liberals trying to convince a group of conservatives that abortion is okay. That would never happen. If a belief is strong enough and stems from upbringing and values, it is nearly impossible for anyone to change it. With time, people may become softer and rationalize a little, becoming more open minded, but I have never known anyone to change their core beliefs or values instantly.