Taylor, in “All Animals Are Equal (But Some Are More Equal Than Others)” provides an interesting criticism of Singer’s arguments about the worth of a life. She focuses on his concept of a “life worth living”, disagreeing with his stance that disabled people live less fulfilling and meaningful lives than able bodied individuals due to their relative lack of ability to value their existence.

Singer’s is clearly a problematic stance. It seems to me that his effort to try and create a unifying theory of how to value life is clashing with how we tend to value the lives of humans in a different way than how we value other animal life, and by extension perhaps how other animals value each other's lives. For example, I don’t think it would be particularly controversial amongst a pack of wolves to leave behind one of their own if that individual is physically incapable of keeping up with them. In contrast, humans tend to take care of our sick and elderly in such situations. I don’t think that means that non-human species value life any less than us, rather that they have a different constellation of values that guide their existence.

I think this relates to Singer in the sense that determining the “worth of life” based on how much someone theoretically values their own is a near impossible task. So many conditions other than cognitive or physical ability determine how much an entity values their own life, and I think in many ways we will never know the full extent of how other animals think about their own existence. I think life in itself is valuable, and Singer’s attempt to try and place a hierarchy of value on that is misguided.