The possibility of free action

Tese de doutoramento, História e Filosofia das Ciências, Universidade de Lisboa, Faculdade de Ciências, 2015The present dissertation develops an agent-causal libertarian theory of action and free will. The backbone of its argumentative structure is that 1) there can be no agency without an agent-cause; 2) there can be no agent-causation without indeterminism; 3) hence, libertarianism is the best option for any realist view about action. The first step in this argument is a defense of agent-causalism. I develop a taxonomy of behavior and agency and argue that both libertarian and compatibilist event-causal accounts fail to provide an adequate description of the differences we find between non-actional behaviors and full-blooded actions. Agent-causal accounts, however, are usually met with suspicion because of their requirement of an irreducible agent with downward causal powers. My second step aims to respond to this concern by presenting a scientifically informed account of emergence as a way to show that the natural order of the world is compatible with the existence of irreducible and causally effective entities, such as the agent’s self. I defend the thesis that natural supervenience does not have to be challenged by this possibility, as downward causation requires only the break of causal closure and bottom-level indeterminism. I argue that both these conditions are unproblematic. The third step is the contention that we have many reasons to believe that consciousness is an emergent property. Moreover, the unity of phenomenal experience suggests the existence of a unified self as the bearer of conscious properties. The conscious self is the irreducible substance-cause who exercises its causal power over the alternatives left open by the probabilistic laws governing its neural substrate. When the conscious self intervenes, agency happens. When it is passive, bodily movement reduces to mere behavior. Given that the requirement for fundamental indeterminism renders my account of agency an incompatibilist account of free will, the final step of my dissertation is the assessment of the classical objections against libertarianism. After analyzing the most important arguments for and against contemporary views akin to my own, I respond to all the objections and conclude that agent-causal libertarianism is the most plausible and satisfactory view of how actions are possible and free