Review: Sentientism – for whose sake? Ethics, sciences, and crypto-teleological fact-value bridges, illustrated by the research about sentience in invertebrates

Sentientism is the most influential position in animal ethics. It presents sentience as decisive for integrating animals in ethics. Nevertheless, its significance for animal ethical argumentation is not quite clear. Does it mean (a) that sentience is a valuable state, which awards sentient individuals the moral prize of something like ‘intrinsic value’? (b) Or is sentience an empirical fact that informs how animal welfare can be adequately realised in samples of certain species? (c) Or does sentience explain psychologically why humans identify emotionally with singular animals? Additionally, the questions show how different animals are addressed, namely (a) as individual units of sentience (individuality), (b) as representatives of certain species (exemplarity), and (c) as unique relata in distinguished human-animal relationships (singularity). Every suggestion of the use of sentientism faces specific challenges: (a) Sentience used as a foundational value premise is philosophically confronted with the fact-value-fallacy. Taken as an absolute value, sentientism may even threaten the status of the sentient individual for the sake of the ideological status of a world without suffering. (b) Sentience in the animal ethical welfare application perspective asks for an evidence-based (neuro-)biopsychological terminology to operationalise the boundary of sentience in animal welfare research, and is confronted with the other-minds problem. For the sake of the individual animal, it has to refer to the specific characteristics of its species. (c) Human-animal relationships have to face the risk of emotional abuse and sentimental anthropomorphism. We must therefore carefully examine the question: For whose sake are not only companion animals regarded as unique – for the sake of the animal or for the sake of human emotional needs? – The range of challenges signals a loss of comprehensive value orientation in modern times. In view of a deeper understanding of the value crisis, the paper starts with a historical reconstruction of the philosophical implications of the transition from natural teleology to modern science. Initially, the ancient conceptual origin of sentientism – the anima sensitiva and its position in a natural philosophical teleological order – reveals sentientism as an isolated fragment from the broken Aristotelean scala naturae. Understanding Aristotle’s highly influential natural teleological metaphysics and its destruction by the rise of modern science can explain how a common crypto-teleological language generates argumentation patterns that are problematic today. A consideration of Kant’s epistemological critique of natural teleology, and his inclusion of animals as sentient beings in a self-reflective modern ethics, may help to clarify the roles of ethics, (bio)sciences, and teleology in enlightened animal ethical argumentations concerning sentience and animal welfare