Nicolas of Cusa wrote De Concordantia Catholica in 1433/34, and it contained pretty revolutionary political ideas:
Going beyond tradition and canon law, he argues on the basis of people’s natural freedom (“men are by nature equal in power and equally free”) that all governance comes from the consent of the subjects. This argument to explicitly institutionalize consent is Nicholas’ original contribution. He follows it with proposals on representation that move from representation as virtual impersonation to representation as delegation based on those represented selecting their representatives. This is one of the first explicit statements in the West of the institutional limits to be placed on rulers and of the idea that people must consent to their representative institutions. Even after he changed allegiance to the side of papal supremacy, Nicholas used his ideas to argue in later brief writings that Basel was not truly representative and that consent was embodied in the college of cardinals.
Why did he change such modern concept of representative government to papal supremacy? Did he write about it in any philosophical work, or does the SEP refer just to political deeds?