A hybrid theory is any moral theory according to which different classes of individuals ought to be treated according to different principles. We argue that some hybrid theories are able to meet standards of psychological plausibility, by which we mean that it’s feasible for ordinary human beings to understand and act in accord with them. Insofar as psychological plausibility is a theoretical virtue, then, such hybrid theories deserve more serious consideration. To make the case for this view, we explain what (...) psychological plausibility is and why we might value it, why the human/animal divide appears to be an entrenched feature of human psychology, and why Robert Nozick’s hybrid theory doesn’t go far enough. Finally, we make the case that a more promising psychologically plausible hybrid theory, with respect to humans and animals, will be (at least) at tribrid theory—that is, positing three domains rather than two. (shrink)

The issues of climate change and environmental degradation elicit diverse responses. This paper explores how an understanding of human moral psychology might be used to motivate conservation efforts. Moral concerns for the environment can relate to issues of harm or impurity . Aversions to harm are linked to concern for current or future generations, non-human animals, and anthropomorphized aspects of the environment. Concerns for purity are linked to viewing the environment as imbued with sacred value and therefore worthy of being (...) protected at all costs. While both harm-based and purity-based framings of environmental issues can sometimes backfire, we argue that making these moral concerns salient can nevertheless bring about moral responses to environmental issues. In sum, scientists' emerging knowledge about the moral mind can be used to facilitate the sustainable conservation of the planet. (shrink)