it seems that on your view it should be impossible to act according to your preferences, but morally wrongly. [emphasis added]
As stated, this is correct. I don't quite think this is what you were going for, though ;)
Basically, yes fully true even in spirit, IFF: morality is the only algorithm involved in human decision-making AND human decision-making is the only thing that determines what the rest of my brain, nervous system, and my body actually end up doing.
Hint: All of the above conditions are, according to my evidence, CLEARLY FALSE.
Which means there are competing elements within human brains that do not seek morality, and these are a component of what people usually refer to when they think of their "preferences", such as "I would prefer having a nice laptop even though I know it costs one dead kid."
If we recenter the words, in terms of "it is impossible to decide that it is more moral to act against one's moral preferences", then... yeah. I think that logically follows, and to me sounds almost like a tautology.
Once the equations are balanced and x is solved for and isolated, one's moral preferences is what one decides is more moral to act in accordance with, which is what one morally prefers as per the algorithm that runs in some part of the brain.
So judging from this, the solution might simply be to taboo and reduce more stuff. Thanks, your question and comment were directly useful to me and clear.
Okay, thanks for clarifying. I still have a similar worry though: it seems to be impossible that anyone should act on their own moral preferences, yet morally wrongly. This still seems quite counterintuitive.
I think there’s a confusion in our discussions of deontology and consequentialism. I’m writing this post to try to clear up that confusion. First let me say that this post is not about any territorial facts. The issue here is how we use the philosophical terms of art ‘consequentialism’ and ‘deontology’.
The confusion is often stated thusly: “deontological theories are full of injunctions like ‘do not kill’, but they generally provide no (or no interesting) explanations for these injunctions.” There is of course an equivalently confused, though much less common, complaint about consequentialism.
This is confused because the term ‘deontology’ in philosophical jargon picks out a normative ethical theory, while the question ‘how do we know that it is wrong to kill?’ is not a normative but a meta-ethical question. Similarly, consequentialism contains in itself no explanation for why pleasure or utility are morally good, or why consequences should matter to morality at all. Nor does consequentialism/deontology make any claims about how we know moral facts (if there are any). That is also a meta-ethical question.
Some consequentialists and deontologists are also moral realists. Some are not. Some believe in divine commands, some are hedonists. Consequentialists and deontologists in practice always also subscribe to some meta-ethical theory which purports to explain the value of consequences or the source of injunctions. But consequentialism and deontology as such do not. In order to avoid strawmaning either the consequentialist or the deontologist, it’s important to either discuss the comprehensive views of particular ethicists, or to carefully leave aside meta-ethical issues.
This Stanford Encyclopedia of Philosophy article provides a helpful overview of the issues in the consequentialist-deontologist debate, and is careful to distinguish between ethical and meta-ethical concerns.
SEP article on Deontology