How we change what others think, feel, believe and do
Spiral of Silence Theory
People will be unwilling to publicly express their opinion if they believe they are in the minority. They will also be more vocal if they believe they are a part of the majority. Thus, the more marginalized you become, the less you speak and so spiral into a fully marginal position.
This works because we fear social rejection. and that when a person appears to be rejected, others will back away from them, fearing being rejected because they associate with the rejected person. It also makes marginalization a powerful way of eliminating political and social competition.
Public opinion is the "attitudes or behaviors one must express in public if one is not to isolate oneself, in areas of controversy or change; public opinions are those attitudes one can express without running the danger of isolating oneself."
Noelle-Neumann showed subjects a picture with one person angrily saying, "It seems to me that smokers are terribly inconsiderate. They force others to inhale their health-endangering smoke." Respondents were asked to phrase a response to the statement whilst other 'planted' people were there. When nonsmokers were nearby, many smokers were less willing to openly support smokers’ rights.
If you were on a long train journey, and a person next to you starts to discuss the problems of food safety. Would you join in the conversation, speaking your true opinion? What if it were controversial, what then?
Show people how the views you want them to express are mainstream, and that the views you want them to change are minority and in danger of causing them to be socially rejected.
When you want to say something, say it. Watch out for being maneuvered into a corner.