The Principle of Excluded Middle in Aristotle

In my dissertation, I provide a systematic account of the principle of excluded middle (PEM) in Aristotle. This principle states that everything either is or is not (an ontological formulation) or that everything is either affirmed or denied (a logical formulation). I focus on questions such as the following: How are the different formulations of this principle related to one another? What is the relation between PEM and other Aristotelian principles, such as the principle of non-contradiction? Are there any exceptions to PEM, such as future contingents? What is PEM’s place within Aristotle’s ontology and syllogistic? And how does Aristotle argue against those who deny PEM in Metaphysics Γ 7?