All of us who think that we, that is, 
those of us in this room, have a 
higher moral status than any animal 
accept what I call a two-tier morality. 
That is, we think that we have rights 
that animals don't, and that we are 
owed forms of respect that aren't 
owed to animals. Yet most people think 
that radically cognitively limited 
human beings are above that threshold 
that animals fall below. Most people 
think that the radically cognitively 
limited have rights that animals don't
 have, and that they have what Martha 
Nussbaum, in her talk the other night, 
called "equal human dignity". That 
is, they have some kind of exalted 
status that they share with us, but that
 animals don't have. But of course if
 it's psychological capacity that 
differentiates us morally from animals, 
that can't be true. So if the 
common view, the view that most people 
believe is right, psychological 
capacity and potential can't be what 
matters - they can't be what give us 
the status that we have but think 
that animals don't. So the question we 
have to ask is: What is it that matters?
 What is the basis of our higher 
moral status that is supposedly shared 
by radically cognitively limited
 human beings but not by comparably
 psychologically endowed animals? Now,
 this challenge typically provokes 
some derision and some indignation, but
 I think the best way to respond to
 the challenge is to give a really good,
 clear, decisive answer to it, and then
 that would... that would shut Peter
 Singer up for good... and me. We wouldn't
 have to go on with this anymore.
 We're waiting for that... waiting 
for that really good answer to that 
question. What is the basis of our higher
 moral status that's shared by the 
radically cognitively limited, but not
 shared by higher non-human animals?
 Now, I think that that challenge remains
 unanswered, and I think that's a
 real problem; we don't understand our 
own moral status unless we can give some 
kind of good answer to that question.
