Daily life is full of choices: when to get up, what to have for breakfast, whether to walk or take the bus, which item to tackle on the ‘to do’ list. It can, at times, seem overwhelming to be constantly required to choose between competing options. On top of this there may be a worry about whether we made the right decisions. But what if all this agonising and reflection was in vain, and the choices had already been made for us? What if our sense of deciding on a given outcome was entirely illusory? Such is the advertised finding of a famous set of experiments carried out in 1983 by neuroscientist, Benjamin Libet.
In his experiments, Libet asked his subjects to make voluntary decisions about when to move a finger and to watch a special clock on the wall that recorded the passing of time in milliseconds. Subjects were asked to note the position of the hands on the clock at the precise time they decided to move their fingers. While subjects were performing the task, Libet was measuring activity in the subjects’ supplementary motor areas of the brain. Most of us would have assumed that our decisions come first and direct the onset of bodily movement. However, contrary to expectations, Libet’s results appear to show the sequence starts with the brain’s preparation for movement, followed by the agent’s awareness of the intention to act, followed by the movement itself.
What are we to make of these findings? Should we conclude that free will is just an illusion? Is our conscious awareness of taking a decision just a comforting story we tell ourselves after the die is cast? It all depends on how we understand the original experiment and how we should interpret its results. Clearly, these are important neuroscientific findings, but what do such results in a laboratory setting tell us about real-life decision-making? And even if we accept the relevance of Libet’s experiments, should we be worried by his results?
Is our conscious awareness of taking a decision just a comforting story we tell ourselves after the die is cast?
The first thing to note about brain activity happening prior to awareness of intention to act is that the impetus to act is still coming from you. It is not that your brain is deciding for you: your brain is you. Your brain is the organ that enables you to plan and perform fluent sequences of movement in a complex environment. What Libet’s results question is whether you are consciously aware of your intention before preparing to move.
We are not always conscious of the intentions that guide our actions. Sometimes we discover our intentions in our actions, by the course of actions we find ourselves taking. For example, we are not aware of deciding to get up and get the bus to work. But we do it anyway, and our intention is simply displayed in the actions we undertake. It is not always like that. Sometimes we put a lot of thought and effort into deciding what to do. But these instances may be quite unlike the cases Libet discusses. In his experimental set-up, subjects know what kind of movement they are going to make, and only have a choice about when to make it. Perhaps, they are poised, ready to make a move, and are preparing to take that decision before they eventually plump. They may be asking themselves, “Shall I decide to act now? No… not yet. Now? No. Yes. Now.” Is Libet simply measuring our getting ready to act?
When we have to make an inconsequential decision and are equally ready to go one way or another, perhaps it’s a good thing we can relegate that decision to a more automatic system that produces a definite outcome. We may not know whether to take the street on the right or the left, to choose the fish or the chicken, and we may simply have to plump one way or another. Many of the things we decide to do are implemented at levels of organisation of which we have no conscious awareness. I decide to speak, I open my mouth, and all the words come out in the right order. I have no idea how I do it. But for speed and fluency it is just as well that it is not under conscious control and direction. Perhaps we operate this way more than we think, and that it is the quick, almost instinctive response, rather than our conscious reflections, that makes us successful as agents.
It may be that Libet’s results tell us less about acting freely than they do about the limits of our self-consciousness. It may be harder than we think to have full, conscious knowledge of what we are up to. Consciousness may not always be a reliable guide to our mental lives. Being in a conscious state is one thing: knowing which mental state is another. And Libet’s experiment gives us pause to wonder just what it is the subjects are said to be aware of: the clock, their decision to act, the relation between them, all three? The state of mind that Libet measures may be a far cry from the awareness that usually accompanies our intentions in everyday life. Our intentions shape our actions and those intentions and our conscious knowledge of what we intend usually march in step. But even when they don’t, we may wonder whether that is always such a bad thing.
Barry C Smith FRSA is director of the Institute of Philosophy at the School of Advanced Study in London and participant in the recent RSA Event, 'The Anatomy of an Action: self and responsibility after neuroscience'