Angst
Rambling and inconsistent
I'm not sure why those things preclude the possibility of the existence of other sapient beings. And since human philosophy is, well, about humans, I don't see why it must include ruminations about other sapient beings. There might be some truths that are applicable to other sapient beings, but such universality isn't all that important and I wouldn't expect everything that is now accepted as true about human beings to be rendered invalid just because they are not true for other sapient beings.
See above. It would be far from the total destruction of philosophy or literature or the arts as they are.
There'll be new things to study, yes, but the predominant emotion, I'd imagine, would be excitement. Hardly something that would cause scholars to collapse with an acute existentialist crisis.
Alien ethics and epistemology might well be very different from human beings', but that's fine, unless you're some kind of hardcore absolutist or rationalist that cannot accept such differences at all.
I guess I did write the bolded part more or less like that, which might ironically have been an overstatement in my own excitement.
