Consciousness is awareness of the self in relation to the world in which the self exists. Creating an artificial conscience and limiting it's ability to ensure it's own survival while allowing it to exist only if it is helpful to us is basically like creating a super intelligent slave. It is unethical and highly dangerous. How can we avoid being manipulated by a super-intelligent being to whom we keep asking for solutions to our problems, that sounds unfeasible to me. Even if we designed an emotional brain for that A.I. that would make it feel bad for hurting humans and good for helping them, there is no way to guarantee that it couldn't get rid of it. We are talking about trying to control a being that is incredibly much smarter than any human that has ever existed and will ever exist. If that's not arrogance I don't know what is. I think that's what most people are afraid of when they think of the dangers of A.I.