> Any possible conception of fairness exists entirely with respect to the material circumstances of reality in the moment, the ethereal weight of determinism is not detectable on the scales of justice.
You've just made another coincidental compatibility here, so I'm curious - how did you arrive at only valuing material circumstances? For me, that is explicitly derived from following determinism into meta-ethics which then follows into a consequentialist physicalist view.
> To put it another way, if we lived in a universe capable of libertarian free will, it would not follow logically that we should then amplify the needless suffering of criminals.
That's a different argument. Something else has to underpin that, and I would again be curious what that is, and if that also shares compatibility.
> The questions of what we optimize for are also highly impacted by free will/determinism.
> How so?
I'm still formulating this fully, but essentially it follows from determinism that objective ethics essentially don't exist (I go with error theory here), which then passes off all of practical ethical meaning to the physical state of the universe in relation to what all beings care about, which I suspect is the step that ends up causing much of the coincidence. So for morality, things that humans (and other beings, but we'll set them aside for now) care about are ethics. I tend to focus on happiness, empathy, and fairness, but there's of course a lot more there. Generally, it means moral psychology actually informs ethics quite a bit.
Since I suspect this isn't going to change anything you specifically believe given the compatibility seen elsewhere, let me highlight some specific ethical views that immediately come under intense pressure from those conclusions:
- basically all deontology (Immanuel Kant and others)
- virtue ethics are then limited to admitting to being a practical compromise at best (originally Aristotle but virtue ethics has been on the rise in many modern debates, and this could 100% shape those)
- even many forms of consequentialism make arguments to optimize for a singular thing or one somewhat removed from humans. This highlights the optimization function is not on a single or even a few variables given that humans don't have a single psychological focus. Or maybe we do and we should be spending more of our time in ethics doing psychological research. But all of this derives originally from that conclusion on determinism.
Basically, even a small difference in underpinning can still lead to different focuses and conclusions down the chain of course.