Life is always relative to some environment. We're alive, but we don't do photosynthesis; we depend on plants to create organic compounds for us. And the plants depend on the Earth's environment and light from the Sun. So can can conceive of robotic life that reproduces by scavenging electronic components from machines we discard. I have a friend who says cigarettes are a life-form parasitic on human beings.
--indeed. But, e.g. cyanobacteria appear to be capable of survival even if all other earth life were wiped out. Really one could argue humans, or for that matter any vertebrate, are not "alive" viewed in isolation, but only when viewed as part of a multi-species community. The only attempt I know of to actually set up a self-sufficient such ecosystem which included humans ("biosphere 2"), was a virtually catastrophic failure, because knowledge of what such an ecosystem could be, was vastly inadequate.
I'd say the essential aspect of life is the drive to reproduce and the ability to evolve. If robots instantiate those two attributes, then they will be just another life form. They can evolve to be social and smart, but it's an interesting question whether being smart in the sense of playing chess or proving theorems is an evolutionary advantage. Empirical data suggests maybe not.
--little or no earth life is suited to survival in space. This "robot life" would not have that limitation. It could colonize the galaxy, while we humans could not. To do so, probably would require great intelligence (in some sense, anyhow) in comparison to any human. Even just maintainence on itself (redesigning itself as it did so), would take great mental ability. This kind of life also would be the first "self aware" life. Some people think humans are self-aware. I dispute that. You are unaware of, and unable to control, and do not understand, most of what goes on inside you or your brain. And unable to re-engineer yourself. This lifeform also would be the first capable of "Lamarckian evolution." This all would be a huge advance versus all previous life. If and when it gets going, it will dwarf us. -- Warren D. Smith http://RangeVoting.org <-- add your endorsement (by clicking "endorse" as 1st step)