This has to be one of my favourite reads. You have to keep it in context in terms of the era in which it was written, but the some of the concepts examined are really mind-expanding.
For example, let’s assume a computer is developed that is sentient or self conscious. That stand-alone computer is part of a network that is of an enemy military. That computer is “captured” as an enemy combatant.
How do you torture a machine for information when it cannot feel pain? Well if the only thing that machine has is sentience, you gradually take away the only thing it values: it’s self consciousness. The “fear” of ceasing to be is the only torture available.
If you find a copy, I urge you to have a look.
gaf.