Here’s a fun philosophy experiment:

Put your hand face down on the nearest surface, and let it rest. When you’re ready, after a few seconds, lift your hand up. You can lift your hand when you want. In your own time.

Did you do it? What made you choose that exact moment? What was it that caused the biological chain from your brain, down your nervous system, to your hand?

These questions have concerned philosophers for millennia, but when Benjamin Libet did experiments into this, there were some shocking and eerie conclusions.

To understand Libet’s results, we have to first know that there’s a part of the brain responsible in “voluntary” actions. This area isn’t active in those who suffer from twitches caused by illnesses like Parkinson’s or Tourette’s. This area of the brain, which controls our ‘readiness potential’, activates before every voluntary decision.

So, the experiment. Libet told a group of subjects to lift their hand when they wanted, whilst special electrodes measured their brain and the nerves in their wrist. All subjects were told to note the exact time they ‘chose’ to move their hand. It was supposed that the awareness of choice would synchronise with the ‘readiness potential’ in the brain.

Yet that is not what happened at all. In fact, the ‘readiness potential’ activated 350 milliseconds *before* our awareness of the fact. This means that our brain has decided to move our hand a third of a second before we think we’ve chosen it.

Our body is acting as it sees fit and our consciousness is watching on like an utterly irrelevant bystander. We pretend we’re in charge, that we’re the ones doing the ‘choosing’, but our brain has done everything already.

There are criticisms of Libet, such as how reliably the ‘readiness potential’ part of the cortex exclusively serves voluntary action. Yet the criticisms are all rather inconclusive, and Libet’s work is recognised as reputable science.

So, when you next reach for a biscuit, or smile at a stranger, remember that your brain had already made that decision for you. We might be having a great time thinking we’re in charge, but in reality, we’re just in a cinema, watching our body act out our life…