Then you aren't using the word "irrational" precisely. I think you mean to say, "Not true." But that's different from "irrational."
For a thing to be "rational," it has to rationalize with its own basic assumptions. In logic, we say that a conclusion must "follow from the premises." A claim can be untrue, and yet perfectly rational. For example:
All cats are dogs.
This is a siamese cat.
Therefore it is a dog.
That's not an "irrational" statement, but rather one that is wildly "untrue." It's actually 100% perfectly rational, in that the rational connections are precisely connected in the right way: it's just false, though. Premise one is manifestly false, and so is the conclusion.
But in order to detect the truth of a statement, it has to be rational first. If it is not even rational, we can dismiss it.
That's the case of subjective "morality." It doesn't even arise to meet the very first challenge of being coherent and rational.
but I didn't require that it be "eliminated" before I was prepared to say what I thought morality actually was.
Well, you insisted it was "subjective," but were completely unable or unwilling to explain how it could be rational. And I've done as much for you, so far: I've told you that I think morality is "objective," and when you asked for examples, I gave them.
But to see the rationality, we'd have to talk about the first premises of objective morality; and you've told me you won't talk about God anymore. So we're kind of hung up by your two contradictory wishes.
It would, actually: because it would at least allow me to speak about the first premise of objective morality.I suppose I could accept the existence of God hypothetically if that helps.
And then, I can show the rationality it contains. (We can leave the truth question aside for the moment, so we don't entangle the two different types of criticism: and then you can criticize what you find worthy of criticism.)
So, accepting that I know you will not believe my first premise, I suggest we might look at objective morality this way:
God created all things.
Morality is a thing.
This entails that God also created morality.
The difficulty for you here is actually goint to be the word "thing." We're going to have to ask if being a "thing" can be met by merely being a sociological delusion, or whether we're only going to allow that "things" includes items that exist independently of imagination. I definitely mean to assert the latter, and you, as a subjectivist, would probably want to include sociological delusions in the term "thing" or "real."
But the important point, for the present, is made. Unlike the case of subjective morality, my claim for objective morality is rational, meaning it meets the test for rational validity, even if you insist it's not simultaneously actually true. Of course, it would be of little use for us to hold to a belief that was merely formally valid, but was also false -- as in the case of the cat-dog above. And for the moment, I happily concede that: I will have to show something by way of truth, as well as rationality.
However, we are now further than subjectivism can go: and that's at least one hurdle it has gotten past that subjectivism falls over. So far, so good.