Johnny the Homicidal Maniac is a rather bloody cartoon, and not for everyone, but the main character does hold some interesting philosophical views. For example the following quote:
“Bones and tissue, tubes and fat. All sustained by blood. Nothing more than a poorly tended machine. … Two species under one name- human- separated only by the workings of their minds. This one is human only in appearance, a clever disguise for a simple animal. The real humans are harder to find.”
This view goes back to the problem of other minds, which I mentioned earlier. The problem of other minds is the question of how we can know that the other people in the world are conscious in the same way we are. As you can tell from the quote Johnny is of the opinion that most of the people in the world are non-conscious automations, and that they do not have minds in the same way we do. This view can also be interpreted as a kind of solipsism, directed not at the world but at the existence of minds.
As I demonstrated in an earlier post the behavior of other people is not enough to guarantee that they have minds, at least in principle. Let us consider the view that the mind is distinct from the physical, for example as it is under various kinds of dualism. Under a dualistic view of the mind a world in which some people have minds and some are zombies is in fact conceivable, since there is no aspect of the physical realm that creates the mental substance or forces it to be attracted to human brains. The very conceivability of this situation has in fact caused some people to reject dualism, for example see the article “An Unfortunate Dualist” by Raymond M. Smullyan.
Strangely it is materialism that defeats this kind of mental solipsism. Let us, for the sake of simplicity, consider the kind of materialism where the mind is an emergent property of the operation of the brain (some readings of functionalism imply this conclusion). Under such a view if we compared the operation of our own brain to the operation of someone else’s brain, and they functioned in basically the same way, then we would conclude similar properties would result from their operation. In other words we would be forced to conclude that we both had minds. Likewise an upward causation view, epiphenomenalism, descriptionism, and aspect monism (all variations on materialism) would lead to the conclusion that other people had minds like your own.
From this we can conclude that Johnny, if he has done his homework, is a dualist, assuming that idealism is out of the question.