College of Liberal Arts & Social Sciences Theses and Dissertations

Full Title of Thesis or Dissertation

Aristotle on the concept of life

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Aristotle, life, soul, substance, homonymy


This dissertation addresses an interpretive problem in Aristotle’s ontology of life. Living things are the central focus of Aristotle’s ontology: they are “substances most of all”. Yet Aristotle also claims that “life” cannot be univocally defined: it is a homonymous term. One reason “life” does not admit of a single definition is that it encompasses both mortal forms of life and immortal, divine forms of life (in particular, the gods and the stars). Without a univocal definition, however, “life” seems to lack the conceptual unity required to explain its privileged ontological status. I argue against available interpretations which seek to unify the concept of life by reference to a core or focal case (i.e., the Prime Mover) or by reference to a common principle (i.e., the soul). On my account, the unity of life is grounded instead in the shared ontological structure of active self-constitution. Life is an identity-realizing activity by virtue of which living things have their substance and form. This underlying ontology accommodates all forms of life (both mortal and immortal) while also providing clear criteria for distinguishing living from nonliving things. Further, it unifies the concept of life by establishing a rigorous analogy between plants, animals, human beings, stars, and gods.

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