Re: Aliens: everything you know is... well, "wrong" doesn't even begin to cover it.
The difference is like the difference between software and hardware. In this way, an organism can interact with its environment as a passive non-agent, but this won't create intelligence, because intelligence without capability is wasted intelligence (evolution doesn't like such waste). (I'm referring to intelligence rather than sentience because under this definition insects have a form of intelligence, but absolutely no sign of sentience)