Here I offer a precise analysis of what it takes for a property to count as emergent. The features widely considered crucial to emergence include novelty, unpredictability, supervenience, relationality, and downward causal influence. By acknowledging each of these distinctive features, the definition provided below captures an important sense in which the whole can be more than the sum of its parts.

Behaviorism is dead! Or so claim the majority of philosophers today. I aim to show that they are wrong. ;I defend philosophical behaviorism as an account of our ordinary, pretheoretical concepts pertaining to the intentional aspects of mind. The theory purports to explain in purely behavioral terms what it is for a mental state to be a belief, a desire or a thought, and what it is about the state that gives it its content. Like Rylean behaviorism, it does not (...) seek to characterize intentional states in isolation from one another. It thereby honors the obvious fact that how we behaviorally manifest our beliefs depends upon our desires, and vice versa. Still, the theory is reductionistic in that it ultimately characterizes intentionality solely in terms of behavioral facts which can be expressed in a purely non-mentalistic vocabulary. ;Over the years, behaviorism has been the target of vigorous attack. In what follows, I consider some of the most popular objections that have been raised. These include: putative counterexamples involving paralytics, deceivers, martians and robots which are designed to show that behavioral criteria provide neither necessary nor sufficient conditions for intentionality, the claim mental content is underdetermined by how one is disposed to behave, the intuition that mental states are internal and causally efficacious and, the worry that since qualitative states can't be reduced to behavior, neither can beliefs about those states. I argue that all of these worries can be successfully handled by a theory which remains completely--or, at least, predominantly--behavioristic. ;Although I am largely concerned with counter-arguments, my dissertation is not entirely defensive. In order to bring out the merits of behaviorism, I show how it compares favorably with some alternative attempts to characterize intentionality purely physically--most notably, popular varieties of Functionalism. I am thereby able to conclude that behaviorism not only remains a viable account of mental content, but is perhaps the most viable. (shrink)