While truly intelligent machines are still in the realm of science fiction, it is worth considering the ethics of owning them. After all, it seems likely that we will eventually develop such machines and it seems wise to think about how we should treat them before we actually make them.
While it might be tempting to divide beings into two clear categories of those it is morally permissible to own (like shoes) and those that are clearly morally impermissible to own (people), there are clearly various degrees of ownership in regards to ethics. To use the obvious example, I am considered the owner of my husky, Isis. However, I obviously do not own her in the same way that I own the apple in my fridge or the keyboard at my desk. I can eat the apple and smash the keyboard if I wish and neither act is morally impermissible. However, I should not eat or smash Isis—she has a moral status that seems to allow her to be owned but does not grant her owner the right to eat or harm her. I will note that there are those who would argue that animals should not be owner and also those who would argue that a person should have the moral right to eat or harm her pets. Fortunately, my point here is a fairly non-controversial one, namely that it seems reasonable to regard ownership as possessing degrees.
Assuming that ownership admits of degrees in this regard, it makes sense to base the degree of ownership on the moral status of the entity that is owned. It also seems reasonable to accept that there are qualities that grant a being the status that morally forbids ownership. In general, it is assumed that persons have that status—that it is morally impermissible to own people. Obviously, it has been legal to own people (be the people actual people or corporations) and there are those who think that owning other people is just fine. However, I will assume that there are qualities that provide a moral ground for making ownership impermissible and that people have those qualities. This can, of course, be debated—although I suspect few would argue that they should be owned.
Given these assumptions, the key matter here is sorting out the sort of status that intelligent machines should possess in regards to ownership. This involves considering the sort of qualities that intelligent machines could possess and the relevance of these qualities to ownership.
One obvious objection to intelligent machines having any moral status is the usual objection that they are, obviously, machines rather than organic beings. The easy and obvious reply to this objection is that this is mere organicism—which is analogous to a white person saying blacks can be owned as slaves because they are not white.
Now, if it could be shown that a machine cannot have qualities that give it the needed moral status, then that would be another matter. For example, philosophers have argued that matter cannot think and if this is the case, then actual intelligent machines would be impossible. However, we cannot assume a priori that machines cannot have such a status merely because they are machines. After all, if certain philosophers and scientists are right, we are just organic machines and thus there would seem to be nothing impossible about thinking, feeling machines.
As a matter of practical ethics, I am inclined to set aside metaphysical speculation and go with a moral variation on the Cartesian/Turing test. The basic idea is that a machine should be granted a moral status comparable to organic beings that have the same observed capabilities. For example, a robot dog that acted like an organic dog would have the same status as an organic dog. It could be owned, but not tortured or smashed. The sort of robohusky I am envisioning is not one that merely looks like a husky and has some dog-like behavior, but one that would be fully like a dog in behavioral capabilities—that is, it would exhibit personality, loyalty, emotions and so on to a degree that it would pass as real dog with humans if it were properly “disguised” as an organic dog. No doubt real dogs could smell the difference, but scent is not the foundation of moral status.
In terms of the main reason why a robohusky should get the same moral status as an organic husky, the answer is, oddly enough, a matter of ignorance. We would not know if the robohusky really had the metaphysical qualities of an actual husky that give an actual husky moral status. However, aside from difference in the parts, we would have no more reason to deny the robohusky moral status than to deny the husky moral status. After all, organic huskies might just be organic machines and it would be mere organicism to treat the robohusky as a mere thing and grant the organic husky a moral status. Thus, advanced robots with the capacities of higher animals should receive the same moral status as organic animals.
The same sort of reasoning would apply to robots that possess human qualities. If a robot had the capability to function analogously to a human being, then it should be granted the same status as a comparable human being. Assuming it is morally impermissible to own humans, it would be impermissible to own such robots. After all, it is not being made of meat that grants humans the status of being impermissible to own but our qualities. As such, a machine that had these qualities would be entitled to the same status. Except, of course, to those unable to get beyond their organic prejudices.
It can be objected that no machine could ever exhibit the qualities needed to have the same status as a human. The obvious reply is that if this is true, then we will never need to grant such status to a machine.
Another objection is that a human-like machine would need to be developed and built. The initial development will no doubt be very expensive and most likely done by a corporation or university. It can be argued that a corporation would have the right to make a profit off the development and construction of such human-like robots. After all, as the argument usually goes for such things, if a corporation was unable to profit from such things, they would have no incentive to develop such things. There is also the obvious matter of debt—the human-like robots would certainly seem to owe their creators for the cost of their creation.
While I am reasonably sure that those who actually develop the first human-like robots will get laws passed so they can own and sell them (just as slavery was made legal), it is possible to reply to this objection.
One obvious reply is to draw an analogy to slavery: just because a company would have to invest money in acquiring and maintaining slaves it does not follow that their expenditure of resources grants a right to own slaves. Likewise, the mere fact that a corporation or university spent a lot of money developing a human-like robot would not entail that they thus have a right to own it.
Another obvious reply to the matter of debt owed by the robots themselves is to draw an analogy to children: children are “built” within the mother and then raised by parents (or others) at great expense. While parents do have rights in regards to their children, they do not get the right of ownership. Likewise, robots that had the same qualities as humans should thus be regarded as children would be regarded and hence could not be owned.
It could be objected that the relationship between parents and children would be different than between corporation and robots. This is a matter worth considering and it might be possible to argue that a robot would need to work as an indentured servant to pay back the cost of its creation. Interestingly, arguments for this could probably also be used to allow corporations and other organizations to acquire children and raise them to be indentured servants (which is a theme that has been explored in science fiction). We do, after all, often treat humans worse than machines.