Luke lists "Why extrapolate the values of humans alone? What counts as a human? Do values converge if extrapolated?" as an open question in So You Want to Save the World.
Would the choice to extrapolate the values of humans alone be an unjustified act of speciesism, or is it justified because humans are special in some way — perhaps because humans are the only beings who can reason about their own preferences? And what counts as a human? The problem is more complicated than one might imagine (Bostrom 2006; Bostrom & Sandberg 2011). Moreover, do we need to scan the values of all humans, or only some? These problems are less important if values converge upon extrapolation for a wide variety of agents, but it is far from clear that this is the case (Sobel 1999, Doring & Steinhoff 2009).
Thanks!
Of course, the premise that "humans are the only beings who can reason about their own preferences" could only justify the conclusion that some human beings are special, since there are members of the human species who lack that ability. Similar objections could be raised against any other proposed candidate property. This has long been recognized by moral philosophers.
If it's worth saying, but not worth its own post, even in Discussion, it goes here.