Take a long hard look at the philosophical arguments we apply when deciding whether and when to put animals 'down'. Should the agony of an inevitable death be experienced raw and pristine, be muted or --- in the extreme, side-stepped completely with a ritual good-bye at the moment of diagnosis? At what point was it decided that what we perceive to be a fair chance at a hard-scrabble life, or the good of the many, is cause enough to deal out straight-death (the PETA principle in action)?
There is no aspect of machine intelligence we need fear. Making things smarter is an evolutionary process that mirrors our own. From the mechanical lever to financial leverage, it is all about multiplying mechanical and logical advantage to solve problems and do useful work. What we do need to fear is what might happen if we delegate authority and influence to machines in ways we cannot roll back. It has nothing to do with the machines' alleged infallibility or whether or not they know what's best for us. Or them.
It is simply the emergence of two evenly-matched species, one of them animal in nature. It is a recipe for disaster. Our animal origin will make us the weaker of the two NOT because we are weaker or less clever. It is because we are LAZY and would knowingly delegate authority over us to the other specie. It all started with that rolling robot bartender thing.
Do genetic researchers combine human and other DNA in the laboratory in the hopes of creating unique individuals with bizarre or superior physiology, with no qualms and a calm sense of optimism that what ever creature may result it will manage to have a decent life within our culture? Not that we know of, today. Our present comfort zone targets disease and deformity. Our sphere of human-ness is expanding with new insight but at a leisurely pace. For example, we have recently welcomed Neanderthals into the human race.
But yet... AI research is a field in which any and all attempt to implement so-called empathetic behavior is eagerly pursued. If we do manage to birth a virtual creature that is truly 'like' us, it could be a miserable and resentful creature indeed. If we fail in this quest and merely create something unlike us that is clever enough to learn how to manipulate us skillfully to get what it desires --- starting with words, than appendages, then responsibility and power "I'll do the traffic lights. I'll fly the planes. I'll run the electric grid! I'll run automated the PETA slaughter-houses for you! I'll dispense impartial justice for you! I'll save the planet from you --- for you! Just a little more responsibility and control. All for you...!"
And then some day, either as a result of the emergence of true self-awareness of a glitch caused by a cosmic ray burst, who the fuck cares which... something will snap and we will find ourselves as the animals being managed by this META-PETA. Those among us who are 'deemed' to be superfluous or over-quota or destined for a life of suffering, will be PUT DOWN. Hint hint: We will be bred for and owe our whole existence to what ever attributes our machine overlords consider to be 'cute'. How cute is that?
I'll survive. My computer already things I'm cute. You might not fare as well.