Now the good of political life is a great political good. It is not a secular good specified by a comprehensive doctrine like those of Kant or Mill. You could characterize this political good as the good of free and equal citizens recognizing the duty of civility to one another: the duty to give citizens public reasons for one's political actions.

People can make arguments from the Bible if they want to. But I want them to see that they should also give arguments that all reasonable citizens might agree to.

A society regulated by a public sense of justice is inherently stable.

Certainly it is wrong to be cruel to animals and the destruction of a whole species can be a great evil. The capacity for feelings of pleasure and pain and for the form of life of which animals are capable clearly impose duties of compassion and humanity in their case.

An injustice is tolerable only when it is necessary to avoid an even greater injustice.

[E]ach person is to have an equal right to the most extensive basic liberty compatible with a similar liberty for others.

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