Extending beyond ethical extensionism: A search for the most plausible theoretical basis for any non-anthropocentric, non-sentientist environmental ethic

Among non-anthropocentric environmental philosophers, sentientists believe that the capacity for having affective mental states like desire, enjoyment, and suffering is necessary for moral standing, and non-sentientists disagree. I believe that non-sentientists have been catching the scent, but never the source, of an important moral realization: that we have a categorical, prima facie, and temporally manifold duty of non-interference, a duty to leave (and sometimes make) things be as they would have been, had our agency not quite existed. My aim is not to establish that this duty exists, or that non-sentientism is true. Rather, it is to establish that non-sentientism finds its most intuitively plausible theoretical basis in a particular, agency defined duty of non-interference. In other words, if non-sentientism is true, then this is why.

The dissertation proceeds in three stages. First, I defend two rather conservative meta-ethical claims regarding this duty: that it matters whether it is objective, rather than subjective; and that it cannot be intersubjective.

Second, I explicate and then criticize two popular candidates for the theoretical basis of non-sentientism: ecological communitarianism, and biocentrism. The first suffers because it excludes entities that we obviously would never exclude; and the second suffers because it produces counter-intuitive results, relies on an indefensible axiological premise, and seems to thrive at least in part on the illicit attribution of sentience to non-sentient entities.

Third, I define and defend our newest theoretical candidate. I define it by examining and then eliminating six bad definitions of interference, and by introducing and spelling out a seventh, agency definition, as usefully and in as much detail as a first introduction permits. I defend it as the most compelling theoretical basis of non-sentientism in two ways: by revealing how much new light this agency defined duty of non-interference sheds on the resilient appeal of the six bad definitions; and by showing how broadly, and how precisely, this duty matches non-sentientist intuitions more generally.

I end by exposing two pressing topics for future research: what grounds we have to believe that this duty actually exists; and what the normative ramifications might be if it does exist.