"When we try to determine how justice can be advanced, there is a basic need for public reasoning, involving arguments coming from different quarters and divergent perspectives. An engagement with contrary arguments does not, however, imply that we must expect to be able to settle the conflicting reasons in all cases and arrive at agreed position on all issues. Complete resolution is neither a requirement of a person’s own rationality, nor is it a condition of reasonable social choice, including a reason-based theory of justice."