A few days ago, I entertained a brief discussion on the nature of the human person, as opposed to the nature of machines. People seem surprised (and upset) that the most common version of the "humans have souls" argument says that animals don't have souls.
Since this argument is in question here, let me try to explain it in more detail.
If you say "humans have souls, which is what makes them different from machines", then you can't believe that animals have souls. Why? Because scientists have already created machine animals, such as robot dogs and...robot cats.
But seriously, there are robot flies that look like flies and act like flies. So in a sense, scientists have a point when they say animals are just complicated machines; after all, they've duplicated the "machinery" of a fly.
If having a soul makes you different than a machine, then flies don't have souls. Because flies are basically machines. Kind of.
Anyway, that's the argument. You can't build a perfect robot human, because humans have souls. But scientists have built perfect robot animals. Therefore, animals don't have souls. They're just complicated machines.
I don't really support this argument--I think animals are more than just machines--but that's how it goes.
In any case, I think the "humans are different than machines because humans have souls" argument isn't going to be settled, until we get a good definition of the word "soul". Right? Right! Because if two people disagree on what a soul is, they'll probably disagree on whether or not animals have them.
So here are some common definitions of "soul":
1. Aristotle says the soul is the source of knowledge in humans. If you have a soul, you can make logical deductions. Therefore, animals don't have souls.
[Technically, he says animals have a different type of soul than humans do, but let's not get complicated.]
2. Cicero (or someone like him) says the soul is the animating principle of the body. In other words, if something has a soul, it can move by itself. These people say animals have souls.
3. Isaac Hayes informs us that he is, in fact, "a soul man". The psycho-spiritual aspects of this claim have yet to be fully explored.
What do you readers think? What is a soul? Let me know.