Just finished listening to Love and Sex with Robots by David Levy. It was somewhat interesting. I'd give it a 3 out of 5.
A solid part of his thesis is that if something has life-like characteristics, we instinctively think of it as alive. Even if we know consciously that it's a robot, our brains use the same subconscious circuits as for real living things. It's not uncommon for people to project human qualities onto inanimate objects (eg. "Damn computer, why are you doing this to me!").
Supposing that we can someday have sophisticated robots that are autonomous and intelligent, what sorts of rights will we give them? Will it be illegal to "kill" a robot? Could someone go to jail for raping a robot (the book discusses sex with robots, as the title suggests)?
The answers seem obvious to me. Or at least the factors to consider are obvious.
Perhaps the most fundamental human motive is reproduction and the survival of one's offspring. Indeed, the whole sex-with-robots idea is a result of hijacking the human drive to reproduce. But it doesn't stop at sex; the reproductive instinct continues with investment in one's offspring to increase their chances of success (grandchildren, etc.). This all sounds very unromantic, but rest assured that all the accompanying emotions (lust, love, protectionism, pride, jealousy, etc.) are part of the evolutionary machinery that gets the job done. So, robots will not enjoy the same rights as humans because there is no genetic investment.
We will, however, invest in robots in other ways. Not just financially, but socially. Consider a well-trained family dog. A dog is not very closely related to its human owner, but the owner and dog have formed an attachment because of the time that each has invested in the other. We bestow some rights onto dogs, but dogs typically have fewer rights than humans. I argue that the rights afforded to something are proportional to the human investment in that something. Children are no different from dogs and no different from robots, except for the amount of investment.
In the end, ethical decisions must have a sound basis in evolutionary stability. That is, ethical decisions should be made in a way that promotes our own genes and memes. Everything outside that is simply missing the point.