On the "objective vs. subjective" question, I think that this issue should not be confused with "simple objective relationships vs. amazingly complicated objective relationships."
I mean, if there are so many objective variables involved that it's impossible to make reliable predictions before the fact, and difficult to agree about causality after the fact (so that you're forced to throw up your hands and agree that "correlation does not equal causation"), it doesn't automatically mean that the matter under discussion is "subjective." It means that the matter is damn complicated.
To me, "subjectivity" comes into play when we are trying to compare the importance of different valuable things, and arguing about which should rank highest on the scale of value.
For example, which of these three is MOST IMPORTANT:
- The freedom of religious belief?
- The freedom to have gay sex?
- The freedom of the press?
Some people would argue for freedom of religion is of greatest value, because in its absence, the state purports to OWN YOUR CONSCIENCE.
Others retort that freedom to have gay sex must be more valuable than the other two choices, because when such freedom is absent, the state not only owns your CONSCIENCE, but owns your GENITALIA, too!
And still others argue that press freedom is the most valuable of the three, because when the press is free, the freedoms to worship as you want and to make love as you want will be more easily secured and protected from state interference.
(And, finally, still other theorists would say that private ownership of land ranks as more valuable than any of those three freedoms, because it provides a place of untouchable sanctum where individuals can worship, have sex, or publish ideas; and others would say that private property, in turn, can ultimately only be guaranteed by the individual freedom to carry a gun...)
So, in my view, things become subjective when you're talking about "the value of different values" -- there may truly be no objective reasons for saying that a person ought to cherish one thing more highly than another.
As an example of a question that is (by my definition) NOT truly "subjective", but perhaps involves too many objective variables for us to reach a clear answer: Did the 2003 SCOTUS decision Lawrence v. Texas (which decriminalized sodomy in all U.S. states) make life better for American homosexuals?
Some people would say that, logically, the decision must've caused some theoretical improvement. But a counter-argument is that the practical effects of the decision were nearly zero, because:
- the anti-sodomy laws had been so rarely enforced
- "Don't Ask Don't Tell" affected objectively larger numbers of homosexuals
- popular TV shows with well-liked homosexual characters, such as Will and Grace and South Park, may have changed the feelings of the heterosexual majority far more significantly than any government action did
...and so forth. So, there are too many variables to clearly prove "causation," yet the individual variables can be quantified and discussed in objective terms.