Dan's second e-mail is the kind of thorough argument that he should've started with. It reads very differently after editing, so the response you'll see tomorrow doesn't respond to a lot of the arguments that initially got lost in the shuffle for me.
But if I had to respond to this text, there are a few things I'd add to my response of tomorrow:
1) "If you revisit the Prophets you'll see that the just society Judaism envisions has never been achieved anywhere at all." But the prophets didn't envision a social justice society like Dan wants, either. Again, to use the most basic element of discrimination and argument, the prophets didn't want gays around in their ideal society.
2) It's quite common to contextualize Maimonides and others when reinterpreting their ideas of <i>halacha</i>. They had different values, people say, so we can understand their <i>halacha</i> as deriving from those values and thus adjust or reject certain elements of their <i>halacha</i>. Dan's contextualization here is quite different. He's saying we should draw a lesson from the values, and then contextualize the values, and in doing so is trying to have it both ways. At that point, it's no longer really about Maimonides' values, but finding inspirational quotations no matter they're meaning, as with "justice, justice, shall you pursue" from the first day.
3) "In other words, Torah law is only partially set in stone, and is equipped to change with the times." Doubtless, but in saying that because we can alter it so much, we can understand social justice as a major element of it, one's creating a circular justification.
4) As to Dan's arguments about Kook, obviously they're entirely subjective, but moreso they're more of the same citation of values while adjusting those values.
5) He lists a bunch of theological principles, and the e-mail now says they "amount to a tradition of social justice." That's far from true. For one thing, other than <i>b'tselem elokim</i>, none of them equalize Jews and non-Jews. And I really don't get how repentance, <i>lifnei iver</i>, rebuke, the reason the courts avoided the death penalty, Abraham's iconoclasm, or Moses's murder of an Egyptian slavemaster have anything at all to do with social justice. And in any regard, he's really put together a very small list.
6) Throughout this and his earlier post, Dan continually cites democracy as a fundamental value in ancient Israel. I don't know where he gets that. Jews lived in monarchies. Laws weren't established in a fundamentally Democratic fashion, nor were judges made in one.