The natural distribution is neither just nor unjust; nor is it unjust that persons are born into society at some particular position. These are simply natural facts. What is just and unjust is the way that institutions deal with these facts.

The claims of existing social arrangements and of self interest have been duly allowed for. We cannot at the end count them a second time because we do not like the result.

Peace surely is a good reason, yes. But there are other reasons too.

When the basic structure of society is publicly known to satisfy its principles for an extended period of time, those subject to these arrangements tend to develop a desire to act in accordance with these principles and to do their part in institutions which exemplify them

There are various ways you might define the common good, but that would be one way you could do it.

A comprehensive doctrine, either religious or secular, aspires to cover all of life. I mean, if it's a religious doctrine, it talks about our relation to God and the universe; it has an ordering of all the virtues, not only political virtues but moral virtues as well, including the virtues of private life, and the rest. Now we may feel philosophically that it doesn't really cover everything, but it aims to cover everything, and a secular doctrine does also.

The circumstances of justice may be described as the normal conditions under which human cooperation is both possible and necessary.