Do you suppose that, as a general matter, people ought not to kill each other?

If you are like most sane adults, then you do suppose that people ought not to kill each other, and in addition, you most likely do not kill, and have not ever killed, another person. However, if you are like most sane adults, you recognize that, despite your general principle that people ought not to kill other people, you know that there are particular circumstances that may require you to override that principle and accept that some people must be killed. Typically, most people will say that if another person is about to kill them or someone they love, then whatever force is necessary to stop that person, up to and including lethal force, would be justifiable. Many people would make other exceptions to the general principle against killing other people.

Still, most people will hold, as a general principle that, barring extreme circumstances, killing another person is something they will not do, because other people ought not to be killed.

Now, there are people, like myself, that hold, as a general matter, that in addition to other people, other animals also ought not to be killed. Obviously, if there are exceptions to the general principle against killing other people (as there is in the case of self-defense) then there will also be exceptions to the general principle against killing other animals. Therefore, if a person who held that, as a general matter, insects ought not to be killed, that person could still believe that people would be justified in killing malaria-carrying mosquitoes who were a threat to human beings.

People who think that other animals, both human and non-human, ought not to be killed, are neither crazy nor extreme. They happen to think that all conscious life is worth living – for the being who is conscious – and that, unless there are extreme circumstances that would justify otherwise, conscious beings ought not to be killed. Who are conscious? All those who have experiences of their own lives.

There are some serious arguments that can be made against this position, although I have yet to find one that is convincing. However, “I like the taste of chicken, therefore it’s okay for others to kill chickens so I can eat them” or “People have always killed other animals in order to eat them” are not serious arguments. Why not? Because some people can say that they like the taste of human beings or that people have always killed human beings, so therefore it must be okay to kill and eat human beings. But it isn’t okay to eat other human beings, because as a general matter it isn’t okay to kill them, as we have already agreed.

Therefore, if it isn’t okay to kill other human beings, then either it isn’t okay to kill other animals — or — there must be something different about other animals that makes it okay to kill them.

Now, one can’t just argue that it is because other animals are not human that it is okay to eat them. That doesn’t answer the question, it just avoids it. Besides, we can easily imagine some other being, different from humans, who are nonetheless not the sort of being it would be OK to eat. The easiest way to think of this is to imagine an opposite hypothetical situation.

Picture some alien beings, far more advanced than humans, visiting earth for the first time. Even though we would be radically different from them, we wouldn’t think that difference alone would be enough to justify them eating us. We’d think that, since we were conscious beings who value our own lives, that we ought to be able to live those lives, even if some other creatures were incredibly more advanced than we were. However more advanced the alien race might be, we would still be conscious of our experiences in life, and we would value those experiences, and we would act in ways meant to keep ourselves having those experiences.

If those alien beings wanted to eat us anyway, but if before they could eat us they would have to justify it somehow (to some interstellar court, say), what case would they be able to make? That because they were more advanced than we that that alone was enough to justify them eating us? That doesn’t seem right. We don’t think that eating other people who happen to be severely mentally enfeebled would be the right thing to do. Most people are certainly more advanced than those who are severely mentally enfeebled, so simply being more advanced than another does not justify our eating them.

What else could justify advanced aliens eating comparatively simple-minded humans? That humans taste good? That aliens have always, for a long, long time, eaten other creatures all across the galaxy? I think there would be no impartial court that would accept such reasons. Could it be that it is because human beings can claim their own lives – because they can speak for themselves and make their own reasoned and rational case for survival – that they ought not to be eaten? No, that couldn’t be it either, because we’ve already agreed that people who are severely mentally enfeebled ought not to be eaten and those unfortunate souls aren’t able to make their own reasoned and rational case for survival.

The only reason that human beings ought not to be eaten is that they are the sorts of creature who have experiences in and of their own lives, experiences that they value and which they act in ways to continue having. This is what connects all forms of conscious life and it is the common thread that demands that as we treat one sort of being, so should we treat all sorts of beings in relevant ways.

That means that if we would not deprive a human being of food, water, and shelter, we ought not to deprive another conscious being, an other-than-human being, of those things. That means that if we would respect a human being’s life, and not kill them, then we ought to respect the lives of other-than-human beings and not kill them either.

That doesn’t mean that since human beings ought to have the right to vote in order to choose their government that any other-than-human being ought to have the right to vote. Choosing one’s government isn’t relevant to the other-than-human beings who live on earth, and they aren’t at all concerned with choosing a government. They don’t even know what government is. But neither do very young children. Just in case we don’t grant very young children the right to vote that doesn’t mean that we deny very young children food, water, and shelter, or that we don’t respect their lives. Just in case we don’t grant other-than-human beings the right to vote that doesn’t mean that we should deny them food, water or shelter or that we shouldn’t respect their lives.

On Earth, we are like the imaginary aliens and all the other-than-human beings are like us. We are far more advanced than all of our earthly relatives, that’s for sure. However, just because I am writing this on a computer, you are reading it on one, and none of the other-than-human beings are able to, that doesn’t mean that other-than-human beings do not value the experiences of their own lives. They do value those experiences, and unless we must act in self-defense, we have no good reason to deny them the opportunity to continue having the experiences they value.

The other animals who share this planet with humankind have as much right to live here as we do. They are, like us, the sorts of beings who have experiences in their own lives, who value those experiences, and who demonstrate by their actions that they want to continue having those experiences. The least we can do is let them.

Image Source: Keven Law/Flickr