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Free Will and Consciousness

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The topic of free will has been a central issue since the beginning of philosophy: How do rational agents exercise control over one’s actions and decisions.

In “the precise of the illusion of conscious will” (2004), Daniel M. Wegner explores the idea of apparent mental causation. He argues that if a thought arises just before an action takes place, if it is consistent with the action and the exclusive salient cause of the action, we will regard ourselves as the agent of the behaviour.

Libet (1985) showed in his experiment that conscious perception of reality lives about half a second in the past. He concluded that we could not have free will, since our brain already comes into action, before we have consciously engaged in the idea. He offered however, as some kind of last hope, the veto right of the free will. The same effect has also been found by Cunningham et al. (2001). In a computer game, similar to space invaders, participants had to use a computer mouse with a half second delay. When the delay was removed, the participants reported that the hand moved before they had consciously made that decision.

So does free will exist? If we live in the past and we falsely attribute behaviour to ourselves that we had no influence of, how can we propose that we are consciously in control of our behaviour? Is consciousness but an epiphenomenon?

I believe that these findings have to be interpreted very carefully. Although they offer intriguing hypothesis about how and why we act, we should not, in a hurry, remove consciousness from the picture. When lifting your finger, as done Libet’s experiment, the motor program running will be automatic, although the decision to do so might be conscious. But do participants really make their conscious choice a few milliseconds before the execution? I believe that they will execute the task in a mental simulation as soon as they are told what will be expected of them in this experiment. So the “causal decision” to execute the movement might be the activation of the action potential itself, not the conscious report of the decision to life the finger. The original decision to lift the finger at that time might have occurred much earlier. The ultimate decision to do so, by putting the body in such a state as to engage in this behaviour, was conscious.

I can only speculate how this mechanism actually could word, but in the computer world there is something called “cronjob”. This is an automatic program that is set to run at a specific time. Its much like always taking your medication at a specific time in order not to forget it. After a while you will remember it automatically at the given time. Thus consciousness might be able to implement such timed processes. If you think about consciousness pulling the string in the background, the half-second delay of the perception does not pose a huge problem. It does however, if free will necessarily requires consciousness to be online “in realtime” to make decisions.

In the computer experiment of Cunningham et al., involving the mouse delay, it is important to plan ahead because the participants know that they will have to cope with a delay. They ordered an action before it actually took place. They did so consciously and also successfully. We might just have adjusted to that specific delay between action and perception very well, because it feels natural to us. As long as consciousness can rely on automatic processes to carry out the proper motor behaviour, it does not need control in real time. Nørretranders (1999) also believes that speed is an important issue; he believes that “ Things that need to happen quickly happen subconsciously.”. Because adjustments of motor behaviour do not require conscious thought, they are not subject to the 500 ms delay.

Backdating perceptions might rather have other practical implications, for example to enhance structuring the environment in meaningful ways. The results of Wegner’s study can be interpreted in this way. Although Wegner’s studies show that our attribution of agency to action can be fooled, It might rather be the case that perception is fooled. I am not convinced that this requires the necessary conclusion that we do not have free will. As seen with the mouse delay, the “natural perception delay” can be altered. In the patient with clinical condition this alteration might include all senses and be persistent. I therefore conclude that consciousness is not an epiphenomenon, but an integral part in the selection of behaviour.


Libet, B. (1985). Unconscious cerebral initiative and the role of conscious will in voluntary
action. Behavioral and brain sciences 8:44, 529-566.

Nørretranders, T. (1999). The User Illusion, Penguin.

Wegner, M. (2004). Précis of The illusion of conscious will. Behavioral and brain sciences, 27, 1-11.

Written by Martin Metzmacher

November 7, 2007 at 1:14 am