For (2), I hold the opposite belief, and here's why:
* Natural Intelligence (NI) exists today without violating the laws of physics, therefore it should be possible to re-create it using raw materials available on Earth.
* NI evolved gradually, starting from simple neural ganglia to move an organism towards food and away from danger. Therefore, there's at least a path to go from amoeba to human intelligence (and maybe super-human too).