Glaucon,
This is how I would describe my disagreement with earth.
He is saying that now rights are objective because people have agreed that we have them. When it is pointed out that they are not objective, he will mention practical consequences of 'rights' such as that he can vote or if he is murdered there will be a trial. The problem for me with this is that there are objective consequences of people believing that there are 'rights', of course, but that the rights do not gain some objective status. And I mean this in two senses. They have no more ontological status than any other idea does. And they are not objective as in correct morally. They shift from culture to culture, time to time. Rights are claims to inherent qualities in humans (or other things) such that they deserve this or that treatment, etc. These inherent qualities do not exist, or if they do, earth needs to show how and where and when they arose, what they are made of, etc.
At times he responds as if we are saying there should be no laws.
At other times as if we are saying that God must exist.
The irony being that his defense has been very similar to theists who point to people's behavior to prove there is a God and theists who say that without God everyone will act immorally.
I am sympathetic to his reactions to what he thinks we are saying and to what he thinks the implications of our positions are. I think his reactions to these things are fairly reasonable ones. But, as said, these are not the positions we have.
I think he thinks that local, collective decisions about what exists can be referred to as objective because this means that certain objective things will happen afterwards.
I also think he misses the problems inherent in nominalism.
Again, I have sympathy for this, but given his not really reading our posts and that his responses are therefore oddly skewed, I am getting tired of being aware of how he sees things without him seeming to have an interest in making this mutual.