All human knowledge is ultimately based on one thing: shared universal human perception. The scientific method, meaning things like predictions, falsifications, measurements by very accurate and sensitive instruments, reproducibility, repeatability, and so on, is, when you think deeply about it, nothing more than extensions, refinements, cross-checks, and repetitions of that same thing: shared human perception.
Take the electron’s negative charge. How do you know it is negatively charged? You perform this and that experiment and observe the result. But ultimately, that result is still just an experience inside your mind. But an Australian team in a different part of the world repeated the experiment and got the same result." The same result = the same experience as yours in America. So, in the end, that is just shared perception being cross-checked.
You can then predict that it will repel a positively charged thing. Fine, but how do you know this? Just an observed experience inside your mind of the two repelling, and so on.
So, if you cannot trust shared human perception as indicative of an objective reality, then the entire scientific enterprise becomes, at the deepest level, just a massive high precision human dream. Maybe, in aliens’ minds, for example, reality appears very differently and is governed by very different laws.
If the starting point is a collective dream rather than an objective reality triggering those experiences inside you, then everything based on it is still a dream. You can cross-check, predict, falsify, measure, and reproduce a dream that is being created by your own mind, but you are still doing all of those things within the same experiential framework, rather than establishing an objective reality outside of it that is triggering those experiences inside you. If the Sun is just a shared dream, then predictions of the Sun’s movement, observed effects of its existence, or whatever method you use to verify it are just verification of a shared dream, not of an objective thing.
So, if we trust and say that universal shared human perception of something = it is objective, and that all minds, even alien minds, will agree with us about it, for example, they will agree that the electron is negatively charged, that the Sun burns rather than freezes, etc. Then why not apply the same thing to moral awareness?
Don’t we all humans have a universal moral awareness that justice is good and injustice is bad? Even if we awfully disagree about what is just and what is unjust, we all still agree on the general principle that justice is good and injustice is bad across cultures and times. You will never find someone who says, for example, “Betrayal of trust is a very good thing, bro.” He does it and knows internally that it is wrong. You won’t find anyone who says, “Helping an orphan is a very bad thing to do and is evil,” etc.
We all universally have this kind of universal moral awareness, so why not let it be an objective moral reality triggering those experiences inside of us, rather than something we invented to help us survive and cooperate and nothing else!?
If you say the human mind self-invents these moral illusions for our evolutionary benefits, then why not say the same thing about the sensory experiences your mind produces?
Haven’t evolution alos shaped our auditory cortex, for example? So why not conclude that these auditory things we hear are just illusions as well, like morals, and do not correspond to objective sounds?
What naturalists already say about morality can exactly be said about sensory perception.
The mathematical physicist Chetan Prakash proved a theorem that states that, according to evolutionary theory and natural selection, any organism capable of perceiving truth or reality as it actually is would not be more fit than another organism at the same level of biological complexity that does not perceive anything about reality at all, but is merely programmed to be more efficient.
We have been shaped through natural selection to develop senses that keep us alive. If I see what appears to me to be a snake, I will not grab it; and if I see what appears to me to be a train, I will not stand in front of it, regardless of whether there is actually a train or a snake there or not. These representations evolved to keep us alive, so we have to take them seriously. But it is logically mistaken to think that taking these representations seriously means believing that reality is actually the way it appears to us.
That’s why you have people like Donald Hoffman and his interface theory of perception!
So, in a nutshell, if you trust shared human perception as indicative of objective reality – the Sun is an objective thing out there, and its existence triggers those experiences inside our consciousness, and other alien consciousnesses, for example, they will agree with us that it is very hot plasma, produces heat, revolves around the center of the Milky Way, etc rather than believing that our minds self-create illusions that may appear differently in other minds, that also self-create their own worlds, then you should accept objective moral reality that triggers that same universal, shared human moral awareness as well. So even aliens will agree that justice is good and injustice is bad.
And you cannot bypass this issue through the scientific method whether by predictions, falsifications, measurements, reproducibility, or causal contact between yourself and other objects because all of these approaches ultimately rest on a single assumption: that shared human perception equates to objective reality, triggering experiences within you.
But if shared human perception is instead a shared dream, then from the very start, everything built upon it remains merely a dream. Repetitions, extensions, or cross-checks within that dream do not transform it into objective reality; they merely produce a high-precision dream. Science, then, becomes a high-precision dream, and morality a medium-precision dream but both remain dreams nonetheless.