Would the advent of conscious machines would aid humanity, even save it, by leading to the kind of super-intelligence that we can harness to our own ends? Or would it mean the end of human beings, their replacement by creatures with godlike powers? If the former, the end of the human story is more like the deus ex machina of ancient Greek drama, a plot device in which divine intervention saves characters from an otherwise irredeemable tragedy. If the latter, it has more in common with the contrived ending to which the phrase now generally refers: radically incongruent with the events that have preceded it, to sinister effect.
Wes Alwan on Deus ex Machina.