"Citizens can have their own grounding in their comprehensive doctrines, whatever they happen to be."

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You might say that, if citizens are acting for the right reasons in a constitutional regime, then regardless of their comprehensive doctrines they want every other citizen to have justice. So you might say they're all working together to do one thing, namely to make sure every citizen has justice. Now that's not the only interest they all have, but it's the single thing they're all trying to do. In my language, they've striving toward one single end, the end of justice for all citizens.

— John Rawls