As I feel sure someone else has pointed out (having not read all 38 replies previous to this one), everyone has beliefs. In direct, interpersonal interactions with other people, any way a person acts is based on some belief. I feel sure this author believes that other people are worthy of at least a modicum of respect for their persons and interests.

Beyond those kinds of relationships, our social nature imposes upon us humans a requirement for governance. The problem arises in determining what should govern governance among people with differing beliefs about how people should act and why.

Heretofore, humanity has looked to beliefs for the answer, which has meant the beliefs of some being imposed on all. That is an inherently unjust state of affairs.

If curious, "Considering Governance for a Post-collapse Community" arrives at an ethic for governing governance that involves no belief at any point. (here in Medium, but not behind the paywall)