Researchers have created what are popularly known as “minibrains” and more formally known as cerebral organoids. As the popular name implies, the typical minibrain is a pea-sized collection of a few million human neural cells. A full human brain consists of about 85 billion cells. These minibrains are typically spawned by transforming human skin cells into the neural peas. As should be imagined, these minibrains raise serious ethical concerns.
One of the main concerns is that since minibrains are human neural masses, they could have or develop consciousness and thus feel or even think. Since moral status often rests on mental attributes, this means that these entities might someday possess a moral status. The challenge is, of course, determining when they achieve that status. This is the classic philosophical problem of other minds: how do I know that other entities feel or think as I do? Interestingly enough, this problem also applies to a food favorite of my home state of Maine, the lobster.
Thanks to thinkers like Descartes, animals have long been regarded as biological machines that do not have minds or, in some cases, even feel. While scientists now tend to regard higher animals as capable of feeling and even thinking, lobsters are generally seen as being pure automatons that neither feel nor suffer. However, there has been some concern expressed about the suffering of lobsters and Switzerland has banned the boiling of live lobsters. The moral justification is, of course, that boiling lobsters alive is unnecessary suffering. Oddly enough, few take the next obvious moral step: if boiling them is wrong, then killing and eating them would also seem to be wrong.
I am inclined to think that while lobsters are not mentally complex, they do feel pain. The reason for this is basically the same reason I think you feel pain: reasoning by analogy. I know that I, as a living thing, feel pain and dislike it. I note that you, as another human, are like me. So, I infer that you also feel pain and probably dislike it. While lobsters are rather different from me, they do have some similarities: they are alive, they interact with their environment, they have nerves and so on. As such, they probably feel pain as well. It must be noted that there are those who deny that humans think or feel—so denying this of lobsters is not particularly odd. Naturally, the relative simplicity of lobsters does suggest that they do not have a depth of feeling; but pain would seem to be among the simplest of feelings.
The moral concerns about the minibrains and the lobsters arise, as noted above, from their alleged ability or potential to feel. The epistemic concern is, of course, how to know this. As should come as no surprise, the same concerns arise about fetuses in the case of abortion: the epistemic and moral problem is knowing when the zygote gains moral status. Obviously, if lobsters can have moral status, then fetuses would also get it rather early in the development cycle—at least at the point when they have a nervous system at least as complex as a lobster.
In the case of the minibrains, scientists want to use them for research that is advantageous to humans. This can be morally justified on utilitarian grounds: the advantages gained from the possible suffering of the minibrains is outweighed by the gains to science. In the case of the lobsters, those who eat them would argue that their enjoyment in eating lobster meat outweighs the suffering of the lobster.
In both these cases, it is a matter of competing interests: the minibrains and lobsters presumably would prefer to avoid suffering and death, while the humans want to experiment on or eat them, as appropriate. The same sort of reasoning also applies to abortion: there are competing interests between the woman who wishes to have an abortion and the interest of the fetus in not dying. While it can be contended that the fetus has no idea of interests, the same can be said of simple minibrains and lobsters. As such, the same moral reasoning can be applied in all three cases: it is competition between the interests of a fully developed person and an entity that is significantly inferior in capabilities. As such, the ethics of the minibrains seems to have already been addressed in terms of the ethics of how we treat animals and the ethics of abortion. This, of course, means that there is no resolution—but it is hardly new territory.