I feel like there's a better version of this to be written, but this is what I have so far.
Let's say you are an effective altruist (an EA), looking for neglected areas in which to have impact. It turns out that we have theoretical reasons for believing a certain mysterious sea creature lives under the ocean. We also have many, but not 100% conclusive, sightings of that sea creature. Otherwise we might think that its part of the abyssal plain is uninhabited, and store nuclear waste there. But if it does exist, it will suffer greatly from the pollution.
Ordinarily, an EA might do something like say "Let's come up with some subjective probability estimates -- maybe 60% there is a sea creature, 40% there isn't" and then use that in weighing whether or not to store the nuclear waste there. A possible sea creature can have a significant effect on policy.
I want to consider a metaphysical creature (although, technically, "creature" may be the wrong word, "organism" may be better), which we have good theoretical reasons to think might exist, and of which we also have many sightings, which at least up until now have not been considered 100% conclusive by the epistemic mainstream.
A "metaphysical organism" is simply one which goes beyond physics. Why should we think that there is something beyond physics? When we look at observed reality, we realize that there is such a thing as perceptions of matter, and such a thing as consciousness. We can suppose that really, everything that is is matter, and then consciousness arises out of that. Or we can suppose that everything that is is consciousness, and we simply have perceptions of matter. Or we can suppose that there is such a thing as matter, and consciousness, and the two interact.
It's hard to imagine how matter and consciousness could interact, because they are so different from each other. It's also hard to imagine how consciousness could arise from matter. What's easy to imagine is that we perceive matter -- we are consciousness and consciousness can interact with consciousness.
If I am going to be a philosopher, or an empiricist (someone who examines experience), then all that exists is my stream of consciousness. And yet I observe that there are things which do not follow from me, and so there is some other reality at play than my own. So I am just a bubble of experience, or an experience-body. But I somehow touch other experiences. I change things in my experience-body because I prefer them to be different and I act on that preference. In the way in which I am conscious, I have preferences and act. So whatever it is that modifies my experience-body apart from me, is something that willed that change.
How would such beings connect with me? We could try to use a physical metaphor: an experience-body is like a sphere, and when the surfaces of two spheres touch, there is a connection. But that's using a physical metaphor. If we only use experience-language, it seems most natural to think that when the spheres overlap, what's really happening is that one being experiences exactly what the other one does -- not a copy, but the very same experience. We don't observe ourselves doing this with any other sentient beings. We have experiences that are broadly analogous with those of other sentient beings, but certainly not the exact same. We experience metaphorical copies of what other beings experience.
So then, how do we connect with people? There's some other being that really does connect with each of us, who "serves" reality to each of us. This being is the Metaphysical Organism.
Without resorting to some things I've mentioned in other texts (simantism, legitimism), and which I won't bring in here, it's possible to also believe in many, many beings, who create a web of these shared experiences. My experience body is shared, but probably only in part, by many other beings. Except, when I fall asleep at night, I cease to exist, yet when I wake up in the morning, I am in many striking ways similar to the being who fell asleep the night before. So it seems like there is some being who watches my experience closely enough to recreate me each morning.
It may be more clear to ask, is there one "server" of conscious connection or many / a "peer-to-peer" network? (Or to say that the question is, "Berkeleianism" (one server) "or panpsychism?" (many / peer to peer).) Let's suppose that we can't know for sure which is which. Then what? We might say "50% chance for the Metaphysical Organism" or "50% chance for the many consciousnesses". The exact number is somewhat made-up. But if we're trying to figure out whether to store "nuclear waste" in some quadrant of reality, we should take both possibilities seriously. If we assign subjective probabilities for these that are very, very low, we aren't taking them very seriously. Certainly a person can take a very low subjective probability seriously, although we tend not to. Driving a car is risky but we don't think about it -- but we could.
Whatever probability we assign to the existence of the MO and of the many consciousnesses (to what is basically a variant of Berkeley's philosophy or of panpsychism, respectively), it is nonzero, since we have good reason to think it's one or the other. So, wishing to expand our moral circles to include all sentient beings, we have some reason to act and think as though the MO exists, and that there are many other consciousnesses. This should be a motion, derived from ethical concerns, to consider such beings as possibly existing.
What would it mean for the MO to exist?
The MO would be perfectly empathic with all sentient beings. No gap in understanding like with human empathy. It would endure great suffering -- the first-order suffering of experiencing exactly what each being experienced, and the second-order suffering of thinking about each being.
The MO seems to have a lot more power over our experiences than we do, and could perhaps flood us with endorphins, but does not. This is odd -- why cause so much suffering? The MO experiences suffering exactly as we do, finds it exactly as unacceptable as we sometimes do in the moment. There may be some limitation on the MO's power. One explanation would be that our free will in some sense matters, and that we need to be perfectly in tune with the MO in the long run, or we'll continue to cause it pain. Our dispositions, preferences, come into tune as we decide they should, that decision being the evolution of preference and disposition. So the process takes a long time and is complicated, and involves a lot of pain. What this means is that the MO values us highly (is willing to experience a lot of pain for us).
We don't necessarily know what the MO wants, other than for something like the elimination of pain or betrayal of all sentient beings someday. But having a relationship with the MO seems to be essential to someday coming into tune with it. So to the extent that we believe in the MO, we should try to connect with it. And there should always be some amount that we try to connect with it, at least a few words of prayer once in a while, that do not threaten to take resources away from things we are sure need to be addressed, if that's our concern.
If there are many consciousnesses, then we should do similar costless things (or more substantial things) for all plants, objects, concepts, and forms of matter, all of which might have some kind of consciousness, for all we know. Or those who are more convinced can be more considerate.