It is often supposed that valuable organisms are more valuable if they are rare. Likewise if they belong to endangered species. I consider what kinds of value rarity and endangerment can add in such cases. I argue that individual organisms of a valuable species typically have instrumental value as means to the end of preserving their species. This progenitive value, I suggest, tends to increase exponentially with rarity. Endlings, for their part, typically have little progenitive value; however, I argue that (...) they may nonetheless have persistence value because, merely by existing, they postpone the numerical extinction of their species. Finally, I propose that a sentient endling can have higher lifeworld value than it would have had were it not the last of its kind. This, I argue, is because when a sentient endling dies, very little of its lifeworld is preserved – and this, I suggest, can be a bad thing. (shrink)

It has been a common assumption that words are substances that instantiate or have properties. In this paper, I question the assumption that our ontology of words requires posting substances by outlining a bundle theory of words, wherein words are bundles of various sorts of properties (such as semantic, phonetic, orthographic, and grammatical properties). I argue that this view can better account for certain phenomena than substance theories, is ontologically more parsimonious, and coheres with claims in linguistics.

Species are central to biology, but there is currently no agreement on what the adequate species concept should be, and many have adopted a pluralist stance: different species concepts will be required for different purposes. This thesis is a multidimensional analysis of species pluralism. First I explicate how pluralism differs monism and relativism. I then consider the history of species pluralism. I argue that we must re-frame the species problem, and that re-evaluating Aristotle's role in the histories of systematics can (...) shed light on pluralism. Next I consider different forms of pluralism: evolutionary and extra-evolutionary species pluralism, which differ in their stance on evolutionary theory. I show that pluralism is more than a debate about the species category, but a debate about which concepts are legitimate and a claim about how they interact with one another. Following that, I consider what sort of ontology is required for different forms of species pluralism. I argue that pluralists who deny the unity of biology will require a further plurality of frameworks, while those that ground their pluralism in evolution need only one framework. Finally, I consider what pluralism means for biological practice. I argue that species concepts are tools, and reflect on how pluralism can illuminate the way systematists approach the discovery of new species of yeast. Pluralism can make sense of the way species concepts are used, and can be developed to aid researchers in thinking about how to use the right tools for the right jobs. (shrink)