Unconscious humans, autonomous machines and the difficulty of knowing which animals are sentient

Abstract

The framework proposed by Crump et al. still leaves much doubt about whether invertebrates such as crabs are sentient. For example, many complex behaviours - even in humans - occur without sentience. Also, simple machines could easily meet all of Crump et al.'s eight proposed criteria for sentience. Acknowledging the limitations of what we currently know about sentience is important both for formulating legislation correctly and for advancing scientific understanding of this most puzzling of biological phenomena.