Debunking the "Bereitschaftspotential", the brain signal that seemed to kill off free will

Originally published at:


It might be, if anybody could define what “free will” is supposed to be.


I’m obviously not going to solve the whole free-will conundrum, but I have to say, I’ve always thought that it speaks well of us bags of meat that, when confronted with the whole “you’re a meatbag” argument, our usual response is to shrug and shuffle away on our little meaty feet.

What I mean is, it’s a nice quirk of the fully deterministic universe that us meatbags mostly don’t have to get too twisted up about the whole you’re-a-bag-of-meat thing.

cheerfully walks away whistling a meatbag tune [because the arrangement of particles in the universe so dictated]



But if you choose not to decide, you still have made a choice.


“You know how when you slap or flap meat it makes a noise? They talk by flapping their meat at each other. They can even sing by squirting air through their meat.”


I’m neither a philosopher nor a cognitive scientist, but I’ve been thinking for a while now that the whole question of free will, or lack thereof, is a fundamentally mistaken question. Something akin to having long and convoluted arguments over increasingly complex models of phlogiston and its qualities, when in fact the whole discussion is based on entirely flawed premises.


This reminds me of a story I read a few years ago, where there was a drug that “turned off” your actual conscious brain, but the Bereitschaftspotential part of your brain kept going - to the point where nobody who didn’t know you took the drug could tell the difference. When the drug wore off, the real you would suddenly wake back up, but not really know how you got where you were, or why you were doing what you were doing.

1 Like

Oh, is that what inspired Ted Chiang’s “What’s Expected of Us” ?


For me, free will just means that the future isn’t already determined (which isn’t the same as it being knowable). Did I actually have a choice to write this comment or not?

That an action could have no measurable cause feels wrong to me, so I fall in the camp of free will skeptic.

First, motor planning in parts of the brain (e.g. premotor cortex) absolutely begins before there is any conscious awareness of the movement. Also we are never consciously aware of many behaviors. Whatever this unreviewed PNAS submission says does not change that.

Second, what does that have to do with free will? The vast majority of what we do is unquestionably subconscious, but that doesn’t mean there is no choice or it is predetermined. Ultimately, our future behavior is unpredictable (from within or without), so whether we assign that to free will, god determinism, or material determinism is an unscientific judgement call.


I’m tapping my fingers right now. :wink:


But that’s an entirely different issue. Quantum physics means the future “isn’t determined” the way it was in a Newtonian clockwork universe, but that doesn’t really mean anything in regard to “free will” – it just means there some random noise in addition to genetics and your environment influencing your behavior.

I’d be tapping my fingers right now if I had my stuff with me.

Free will? Free of what?


1 Like

Damn, I’ve been using this to excuse my behaviour for years

There’s no definitive answer to what quantum physics means. I don’t really know what I’m talking about, but it sounds like you are referring to the Copenhagen interpretation of quantum mechanics. There are others of course. My favorite is the we are all just mathematics which comes from the idea that matter is just quantum fields and a quantum field is just math. Another big one is the super-position idea where every possible state exists in different universes and in that model I’m not sure free will has any meaning.

So who knows? In the end I’m not sure it makes a difference if free will is what it appears to be or not.

1 Like