/u/sunagainstgold gave an excellent overview of the problems of studying medieval peasants and discussing some of of the debates surrounding peasant uprisings in medieval Europe. I think if any one thing could be said about medieval peasantry, it is that they would not have seen themselves as some kind of proletariat mass under the heel of a single "feudal" system. That is not to say that peasants did not have political opinions or never considered themselves oppressed. As /u/idjet has commented before about his studies into medieval French inquisitorial records, the medieval peasant was not as incapable of coming to highly individualistic beliefs about their own world (both in religious or political terms). However, the self-conception of the peasantry and their opinions on politics were probably much more locally centered than "public opinion" in modern political terms. An English field worker participating in the Jack Cade Rebellion of 1450 will have a quite different perspective on how England should be governed than, say, a Gascon peasant living near one of the remaining English garrisons in France.