Does a glass bottle have a consciousness? – Of course not.

Does a leaf in the wind have a consciousness? – Of course not.

Does a tree have a consciousness? – Of course not.

Does a bee have a consciousness? – Probably not.

Does a cow have a consciousness? A dog? A monkey? – Hmmm.

Does a computer program which passes the Turing test, i.e., with which you can “talk” just like with any human (so that it will even be able to explain its “feelings” to you) have a consciousness? – Well, people are more inclined to agree that it is “intelligent”, but more hesitant to admit it has a consciousness.

What would an alien from another planet have to do to convince you that it has a consciousness? It might look very different and might even “think” differently. But does that mean it cannot have a consciousness?

When does a person, who is 100% paralyzed, lose his consciousness? Suppose there is no reaction whatsoever to the things in the outside world, does that mean there is no consciousness? What if some brain activity could be measured? What if this activity was lower than “normal”? What would this person need to “do” to prove to you that he still has a consciousness?

Can a machine be “hungry”? What about a simple robot, which moves about in a room and, when its batteries are low, tries to find a power socket. Is it hungry?

I also find the ethical implications interesting. Killing animals is usually considered ok, or at least not a crime (at least if they taste good). Would killing be aliens be considered ok as well? Does consciousness matter for this question?

[If you also find these kind of questions fascinating, check out “The Emperor’s New Mind“.]