Louis M. Guenin’s principal interests lie in moral philosophy, metaphysics, and the philosophy of science. His work in moral philosophy concerns distributive justice and ethical issues in research. A current project consists in a mathematical account of the boundedness, introduced in The Morality of Embryo Use, of developmental potential, of which an ontological view was contributed to the anthology Contemporary Aristotelian Metaphysics. The project consists in attempting to show in detail how boundedness of situation-relative developmental potential becomes discernible upon treating instantaneous developmental stages as outcomes of a random trial, defining a random variable, and observing the least upper bound of the associated probability density function’s support. Related work consists in attempting to understand whether and in what sense there are any “surefire” dispositions. One answer, in the parlance of probability theory, is “almost surely.” Concerning distributive justice, a book in progress will relate the mathematical foundations of consumer utility theory and the social welfare function, then attempt to show that among social welfare functions, the Rawlsian is singular for feasibility. Another project concerns mereology and species. Its burden is to clarify the case against the dictate of extensional mereology that every composite is the sum of its parts, to adduce mereological reasons why a species cannot be a sum or any other sort of whole composed of parts, and to defend the view that taxa are structures.