Moral relativism (2) Rights from wrongs.

Moral relativism(1)
Alan Dershowitz'Rights from wrongs" is provocative, his scope extends to Rawls and Dworkins.

It is more realistic to try to build a theory of rights on the agreed upon wrongs of the past that we want to avoid repeating, than try to build a theory of rights idealized conceptions of the perfect society about which we will never agree. page 7

Where does rights come from? Or , put more concretely: What are the sources of our right?
This question is crucial because in the absence of an authoritative source of rights, such as God, or nature, it is easy to argue that man-made needs of the majority in a democracy. page 5

Rights do not come from God, because God does not speak to human beings in a single voice, and right should exist even if there is no God.
Rights do not come from nature, because nature is value-neutral.
Right do not come from logic, because there is little consensus about the a priori premises from which right may be deduced.
Right do not come from the law alone, because if they did, there would be no basis on which to judge a given legal system.
Rights come from human experience, particularly experience with injustice. We learn from the mistakes of history that a right-based system and certain fundamental rights...are essential to avoid repetition of the grievous injustices of the past. ...
In a word, rights come from wrong. page 8

Dworking's core principle is that government must treat all their citizens with equal concern and respect. This principle is fundamental "postulate of political morality" to which all reasonable people must adhere. page 43

I agree that human equality should be an important foundation stone for any theory of rights, but I would argue that it is an invention rather than a discovery.
A more persuasive argument for the right to equal treatment would be built on our collective negative experience with the wrongs of unequal treatment during slavery, the Holocaust , the Inquisition, and other disastrous human epochs. page 44

Even the claims of some natural rights advocates rest---at least to some degree---on the implicit consequentialist assumption ...A particular right can only be justified as a trump on majority preferences ....if non-recognition of that right will make people worse off(which is my preferred negative reformulation of Jremy Bentaham's "great happiness of the greatest number" postulate. ....
it could be argued that ...tampering with any particular right may endanger the entire package and make people worse off...But it still judges morality by its impact on people---in my favorite formulation , by its impact on preventing the recurrence of wrongs. page 46

"Rights from Wrongs" Alan Dershowitz
So after all it seems he is consequentialist which appeals to historical experiences.

What is interesting is he seems to hold moral relativism; rights are backed up with negative experiences in history of the society. His theory is very attractive. But can he tackle the criticism against relativism?

I think Objectivism or Relaitivism, the point is whatever the authority---- God, human nature, objective moral principle , moral reality independent of people, social agreement , collective negative experience---is, it seems it does not follow the authority necessiates one and only one choice, that it is often possible that two conflicting views are permissible.

Relativism faces troubles when faced with the question why the authority in question is right, what authorise the authority---isn't it the case that the authority is authority because it is backed up with objective truth?
Objectivism faces troubles when pushed in the same way. Why the hell is the authority in absolute sense, or in objective sense right?.
It is often the case that there are cases where there are two conflicting and yet permissible case based on the objective principle. But that is not the only problem. To answer the question, either she has to say because it is objective, which is tautology:she can not say where and how she discovered it(---oracle?) or she needs to appeal to the authority in a relative sense；

This is my ongoing thought. I think I need to get deeper understanding.
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A regulative ideal is one which is reasonably founded in an understanding of human nature. Justice and freedom are similarly ideals. Even though perfect justice may be impossible in the world, our assessment of whether something is just or not is guided by reference to a rational account of what justice is Regulative ideals don't seek to describe how things actually are: instead they refer us to a point of view from which we can access ourselves and the world. page 136 conditions of love john Armstrong.