Objection (4a): Metaphysical Assumptions and Special Value
“Animals are morally less important than humans because they lack special value or dignity – because they were not created in the image of god or are not endowed with immortal souls or are not rational creatures.”
(4a.1) Metaphysical Assumptions Not Shared by Everyone
These are ideologically or religiously impregnated metaphysical assumptions. As such, they are no longer shared by everyone – at least not in enlightened and progressive societies. Since morality is supposed to appeal to and apply to everyone in society, there is little point in premising it on assumptions that are not commonly shared.
Moreover, philosophically speaking, the notions of value or dignity are in limbo – even if they are not premised on other metaphysical presuppositions. As Peter Singer aptly puts it: “Philosophers frequently introduce ideas of dignity, respect, and worth at the point at which other reasons appear to be lacking, but this is hardly good enough. Fine phrases are the last resort of those who have run out of arguments.” Invoking such concepts is therefore fraught with countless difficulties.
(4a.2) Differences of Value only Relevant in Specific Situations
Even if human beings were – for whatever reason – more valuable than animals, nothing could be inferred from this fact for the treatment of animals in general. Instead, such a difference would only seem to be relevant in situations of real conflict or dilemmas (see 2.3). So, if you have to choose between saving, say, a human being or a dog, the alleged greater value of humans would speak in favour of saving the human rather than the dog. But why should this superior value entitle those who have it to inflict suffering on, and kill, those who have less of it or lack it altogether – even outside of situations of real conflict? (And, of course, what we do to animals on a daily basis has nothing to do with such situations of conflict.)
Superior value might make sense as an additional criterion for an emergency principle to reach a non-arbitrary decision in situations of real conflict; but it’s certainly no carte blanche to instrumentalise others who are considered less valuable.