Can we declare that the ultimate moral good is to maximize understanding of deep truths, and all else follows from that?
The main thing that could morally distinguish humans from other animals is that we have more capable brains. Specifically, our brains are able to form abstract models that allow us to understand more of the world than other animals can. The models allow us to answer "how?" and "why?" in a deeper way than any other animal.
Understanding-based ethics is about understanding of deep truths. Making a database of all the blades of grass in your yard, for example, constitutes truth but is very shallow. Deep understanding is more than just a list of facts. It's about the deep structures tying different ideas together fundamentally.
- Lying would be wrong under this system because it directly works against mutual understanding of the truth.
- Murder would be wrong under this system because it deprives the world of a mind that could understand. The greater the mind lost, the worse the offense; this is why it is worse to kill a human than a raccoon. But everyone has their own unique viewpoint and experiences, so it is wrong to lose any life.
- Lesser crimes such as stealing would be wrong because they damage the harmonious functioning of society, which is necessary to support the pursuit of truth. In a poor society, people have difficulty deeply understanding the world around them because they are too focused on scrounging for subsistence.
- Education, research, and free and honest discourse would be ends in themselves.
Say the "best" moral system is X. Suppose, contrarily, that understanding-based ethics is not X. But by pursuing understanding-based ethics, we would best be able to learn of X. The more we understand about moral matters, and the more widespread this understanding among everyone in society, the more widespread adherence to X would become.
So that even if understanding-based ethics is not the best moral system, it would be the best way to reach the best moral system, and transition to it once it is known! So by following understanding-based ethics, we get to hedge our bets.
Understanding-based ethics sidesteps some of the problems of utilitarianism. If you could spend the rest of your life in a delusion box that grants you a feeling of happiness in a virtual world you can't distinguish from reality, should you? Utilitarianism says yes, probably. Understanding-based ethics says absolutely not.
Suffering is just an indicator of a problem, like the "check engine" light on your dashboard. The goal isn't to make the "check engine" light go off; the goal is to fix the engine.