That second word is strange to me

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Just is not on the eye of the beholder. Justice is a value that comes from our nature, it's inside us, we always look for justice. Justice only means that certain thing or concept is succesfully adapted to society. For example, if I say that the fraud has become and accepted practice and even a custom, shuold I make it legal, us course not, because it's against morality, now if you want to discuss the subjective value of morality I'm with you. But let's suppose that it's related to a non-criminal activity, marriage for example. Let's say that this community has been celebrating marriages for a very long period of time, with no essencial variation in the process (that constitutes custom), and registering it in the local parrish. In this case it's not an activity against morality, therefore it's acceptable to establish this new custom as the regular legal canon from now on, and wipe out the old, why? Because what makes differenciates the law from morality is that the law (not justice at all, but part of it) has objective rules, one of them is based on the idea of justice, adjustment to society values and practices, as long as they're moral.
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