Summary of doctoral thesis: My thesis investigates how Aristotle grounds the fixity and eternity of species not only biologically but also cosmologically. These theses seem indispensable given their roles in Aristotle’s explanation of the regularity of nature, his criticism of Empedocles’ primitive evolutionary ideas, and his theological account of how mortal beings in the sublunary world participate in eternity. However, empirical cases reported in Aristotle’s biological works, such as hybrids and spontaneous generation, have been regarded as threatening the theses, since they appear to imply the coming-to-be of new species and the extinction of existing ones. This apparent conflict arises from the assumption that the fixity and eternity of species are biologically grounded in a permanent reproductive series of kind-members. Instead, I will argue that they are cosmologically grounded in the eternal universe without start or end, the eternal and regular motions of its celestial bodies, and the regular and stable changes in climate and habitats resulting from these motions. In other words, the reproductive series provides only epistemic evidence for the theses, whereas their ontological ground lies in cosmological stability. On this basis, I will argue that hybrids and spontaneously generated beings can be accommodated with the fixity and eternity of species, since they recur intermittently but regularly.
Other research interests: Philosophy of Science
