10/7/10

Alfred Mele, Effective Intentions. The Power of Conscious Will, Oxford, Oxford University Press, 2009

Effective intentions
is a book to be praised by everyone who thinks that philosophers should address issues of public interest, in particular when they arise from the advancement of science. Recent developments in the experimental study of our conscious decisions are challenging some widely spread and deeply rooted intuitions about free will. In Effective intentions Alfred Mele, a prominent philosopher of action, claims that there is no conclusive scientific evidence about the causal efficacy of our decisions and, provided we adopt a proper theoretical framework, there are good grounds to defend the freedom of our will. Mele's book is short and accessible, but it is not popular philosophy: it often engages in scholarly debates and discusses technical points at length. However, those who find the conceptual discussions pervading the popular literature on these topics too rough will probably enjoy reading it. The following summary will provide at least a glimpse of its structure.

In a famous experiment conducted by B. Libet, the participants had to make a movement with their right hand whenever they wished. Libet recorded the electrical activity in the scalp of his experimental subjects together with the activity of the relevant muscles, asking them to signal the time at which they consciously initiated the movement. Libet detected a shift in the activity in the motor cortex that precedes voluntary muscle motion (the "readiness potential") about 550ms before the actual movement took place. The experimental subjects reported the conscious initiation of the movement only 200ms before it started.

Experiments of this sort challenge our common understanding (the folk psychology) of voluntary actions: since we take our will to be free, we would expect the movement to depend somehow on the agent's beliefs or desires. This is why these experiments have captured the popular imagination proving that our will is, in fact, not free. As the title of the book suggests, Mele thinks that intentions are effective and follows a twofold strategy to prove it. On the one hand, Mele reexamines the experimental evidence against free will showing that it is not as conclusive as is often taken to be. On the other hand, the philosophy of action constructed by Mele throughout the past two decades allows him to interpret the experiments in a way that preserve the efficacy of our intentions.

As to the former, Mele puts forward the following interpretation of Libet's experiments: the electrical activity recorded in the scalp 550ms before the action starts would rather be a potential cause of a proximal intention or decision, than any of these two. At least, the electrical patterns associated with the pre-conscious brain activity in Libet's experiments are similar to those recorded in other experiments where there seems to be no apparent unconscious intention or decision. It should be something else, concludes Mele: perhaps some sort of causal input of the intention. In a similar spirit, Mele contests the instances of actions in which intentions apparently have an epiphenomenal role put forward by Daniel Wegner, showing that such actions may not count as intentional. But what sort of intentions could these be?

Mele focuses on ocurrent intentions, defined as executive attitudes towards plans, i.e., being settled on executing them. Such attitude, warns Mele, cannot be reduced to any combination of beliefs and desires. Ocurrent intentions arise from decisions when there is uncertainty about the alternatives; if there is none, ocurrent intentions can be acquired without any explicit decision. Hence, proximal intentions (about immediate actions), at least, need not be conscious: when we act by habit, our acts are no less intentional (we are settled on executing them) even if there is neither a explicit decision nor any awareness of our intentional process. Finally, Mele accepts that intentions may have potential causes and still fully contribute to our actions I hope this very simplified summary will at least suggest why, if we accept Mele's approach, Libet's experiments would not exclude, at least a priori, an intentional interpretation. Our intentions may be considered so despite being causally prompted, unconscious or separated from our beliefs and desires.

However, this does not amount to prove that intentions are causally effective in producing an action. Mele invokes here the evidence on distal implementation intentions: there is evidence showing that people meet non-immediate goals in significantly higher proportion if they are state in advance when, where and how will they achieve them. Prima facie, intentions seem to play a causal role in the explanation of these actions ―and Mele argues at length against alternative accounts in which they do not.

Mele closes the book claiming that science has neither shown that free will is an illusion nor that there are no effective intentions: "this is good news for just about everyone", concludes. But probably "just about everyone" (not this reviewer) will be slightly concerned by the admission that our intentions are causally originated somewhere beyond the realm of consciousness. Mele is quite vague about this point, stating just that our decisions may "more proximally initiate an intentional action that is less proximally initiated" by a potential cause of such decisions (p. 69). I agree with Manuel Vargas (see his piece on Mele's book for the Notre Dame Philosophical Reviews) that this is precisely the point that many would have wanted to see addressed.

It is an indisputable merit of Mele to show that the conceptual framework of Libet's experiments, among others, is often imprecise. Yet, by the same token, it is shown that "the conceptual schemes that we use to interpret and explain our behavior" are equally misleading, which is no less unsettling. Mele's conceptual schemes are certainly more articulate, but this book will not allow the uninitiated reader to grasp them in full. However, unlike many others in philosophy, Mele suggests bits of experimental evidence that could potentially falsify several parts of his theory. We can only hope these tests are actually conducted, making this debate progress in a more empirically oriented fashion, even if the news are not always as good as we once expected.

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