Libet's experiment and its irrelevance to free will
There are many - and almost invariably they lack any expertise in philosophy - who think that a famous experiment performed by Benjamin Libet somehow disproves that we have free will. Unsurprisingly, they're wrong.
First, here's the experiment. A person's brain is monitored. If it exhibits a certain behaviour - that is, if a certain kind of event occurs in it - this will trigger the monitor to make a recording of that event. (If no such event occurs, no recording will be made). The subject is then asked to perform a hand gesture - to flex their hand - whenever they wish. However, they are also asked to note when it seems to them that they formed the intention to perform it.
What Libet noticed is that the brain event that triggers the monitor to make a recording occurred slightly earlier than when the subject believed they had formed the intention to perform the hand flex. From this we are supposed to conclude that the brain event that causes our intention occurs prior to, er, the intention. And this somehow shows we lack free will.
This is such a non sequitur I find it hard to comprehend how anyone can be so stupid as to reach that conclusion. But perhaps I'm the stupid one. Let's see....
First, let's just note in passing that as it is a certain kind of brain event that actually triggers the recording, it is no surprise that every recorded instance shows that brain event occurring. And you obviously cannot from that conclude that the said brain event causes the formation of the intention.
But that's by the by. Let's just - purely for the sake of argument - assume that the said brain event does indeed cause the intention. So what? I mean, Libet asking the subjects to form an intention to flex one's hand is an event, and it caused the subject's to form that intention, and it occurred earlier than they will have registered thinking they formed the intention in question. So if that - the fact a prior brain event is causally implicated in the formation of an intention - is supposed somehow to show that we lack free will, then Libet needn't have gone to all the trouble of monitoring people's brains. Just say "form an intention to flex your hand and tell me when you think you have done that". For I guarantee that to anyone to whom you say that will report that, in their view, they formed their intention at a time later than when you issued the request. And that, if Libet's experiment somehow shows we lack free will, would also be sufficient to show that we lack free will, wouldn't it?
Juts to clarify: one could just ask someone "form an intention to flex your hand and tell me when it seems to you that you did so". You ask this question of a subject at 3pm precisely. The subject subsequently form an intention to flex their hand and they report having done so - this occurs at 3pm and 2 seconds. Conclusion: the subject lacks free will because their intention was caused by a prior event.
Have I made a mistake in my analysis?
First, here's the experiment. A person's brain is monitored. If it exhibits a certain behaviour - that is, if a certain kind of event occurs in it - this will trigger the monitor to make a recording of that event. (If no such event occurs, no recording will be made). The subject is then asked to perform a hand gesture - to flex their hand - whenever they wish. However, they are also asked to note when it seems to them that they formed the intention to perform it.
What Libet noticed is that the brain event that triggers the monitor to make a recording occurred slightly earlier than when the subject believed they had formed the intention to perform the hand flex. From this we are supposed to conclude that the brain event that causes our intention occurs prior to, er, the intention. And this somehow shows we lack free will.
This is such a non sequitur I find it hard to comprehend how anyone can be so stupid as to reach that conclusion. But perhaps I'm the stupid one. Let's see....
First, let's just note in passing that as it is a certain kind of brain event that actually triggers the recording, it is no surprise that every recorded instance shows that brain event occurring. And you obviously cannot from that conclude that the said brain event causes the formation of the intention.
But that's by the by. Let's just - purely for the sake of argument - assume that the said brain event does indeed cause the intention. So what? I mean, Libet asking the subjects to form an intention to flex one's hand is an event, and it caused the subject's to form that intention, and it occurred earlier than they will have registered thinking they formed the intention in question. So if that - the fact a prior brain event is causally implicated in the formation of an intention - is supposed somehow to show that we lack free will, then Libet needn't have gone to all the trouble of monitoring people's brains. Just say "form an intention to flex your hand and tell me when you think you have done that". For I guarantee that to anyone to whom you say that will report that, in their view, they formed their intention at a time later than when you issued the request. And that, if Libet's experiment somehow shows we lack free will, would also be sufficient to show that we lack free will, wouldn't it?
Juts to clarify: one could just ask someone "form an intention to flex your hand and tell me when it seems to you that you did so". You ask this question of a subject at 3pm precisely. The subject subsequently form an intention to flex their hand and they report having done so - this occurs at 3pm and 2 seconds. Conclusion: the subject lacks free will because their intention was caused by a prior event.
Have I made a mistake in my analysis?
Comments (35)
Anyway, even though you're wrong and it is not about predicting behaviour, even if it was, how would that show that we lack free will?
For instance, I predict that very shortly I will be told I am an idiot and don't understand anything. When that happens - and it will happen any moment - will I have shown that the person who says this lacks free will?
Here's another prediction. When Libet said, at 3pm, please form an intention to flex your hand, I predict that the subjects to whom he gave this instruction will form the said intention. Does that show that free will doesn't exist? Have I just done what Libet did but without hte need for costly equipment?
Quoting Gregory
Oh, well, okay then. Good point!
Therefore you lack free will.
Bartricks proves we lack free will.
Second: relevance? You did think of a red tomato, yes? Have I just proved - by that - that you do not have free will?
Just Google free will experiments. When I looked into this there were many many of them. If I say "lift a hand" and accurately predict you will lift the left one, and then do this multiple times, this does show something about free will
So, once more, it is 'not' about prediction. The brain event triggers the recording.
It's as I described it. And the inference is absurd. Like I say.
You: yeah, but there are other experiments demonstrating other things. So there!
I don't think you want to understand the experiment(s) so nevermind.
Libet's experiment was discussed in the FreeWill thread : https://thephilosophyforum.com/discussion/comment/503684
Note : even Libet did not claim that his experiment disproved freewill. See link below. But it seems that our conscious freedom may sometimes be limited to a final Veto over the subconscious action potential. In other words, the body has already made up its mechanical mind, but the freethinking Mind still has the final word : yes or no. It ain't much, but it's not nothing. :smile:
"Conscious-will could thus affect the outcome of the volitional process even though the latter was initiated by unconscious cerebral processes. Conscious-will might block or veto the process, so that no act occurs.The existence of a veto possibility is not in doubt."
___Benjamin Libet, the 'freewill' experiment
https://static1.squarespace.com/static/551587e0e4b0ce927f09707f/t/57b5d269e3df28ee5e93936f/1471533676258/Libet%2C+Do+We+Have+Free+Will%3F.pdf
Yes, very confusedly. So?
Quoting Gnomon
Yes, I know. I said many have taken his experiment to disprove free will. I didn't say Libet did.
Are you disputing that many, many, many, people think Libet's experiment disproves free will?
Or are you implicitly suggesting that it is the person who performs an experiment who has final authority on what its implications are (and thus as Libet did not think it disproved free will, that is sufficient to establish that it doesn't, and so my criticism of those who think otherwise is surplus to requirements)?
You. Haven't. Read. The. Article. Right? Yet you think you understand it. Dunning and Kruger.
Me: here's an experiment that many think disproves free will. But it doesn't, because at best all it shows is that our intentions have causal antecedents, which isn't remotely surprising, doesn't require any brain monitoring to establish, and doesn't imply we lack free will.
You: the experiment is about CATS and their number of legs. Which is three.
Me: Er, no it isn't (and cats have four legs, not three - but meh). Can you provide a reference for that?
You: Just put 'cats' into the internet. You'll find lots of information. And you'll see they have THREE legs.
Me: No, a reference to the article in which the experiment is described - a reference showing me that the article is in fact about cats.
You: you clearly aren't interested in discussing the experiment in question. Oh well.
1. R = The brain recording of an intent (to flex a hand) as observed by the experimenter
2. I = The intent (to flex a hand) as reported to the experimenter
R precedes I and so, the experimenter concludes, we lack free will because brain activity to perform a certain act occurs before the intent to perform that act. So, for example. my brain initiates the action to eat a banana much before I intend to eat one.
I suppose the free will wouldn't have been subverted if it had been the other way round - I intend to do something and only after that the instruments register brain activity correlated with whatever that something is that I intend to do.
Two important aspects to the problem:
3. The time delay between recorded brain activity of a particular action (R) and the intention to perform that action (I)
4. The temporal sequence between recorded brain activity of a particular action (R) and the intention to perform that action (I).
Well, from 3, it's clear that time is of the utmost importance and the experimenter has to make sure that errors don't creep in from, say, nerve conduction speeds/time. For instance, how does the subject of the experiment report faer intention to do something? Does fae have to press a button or does have to say it out loud? Do the neural pathways involved in this part of the experiment require a duration of time that matches the time lag between R and I?
What's interesting though is that 4, R precedes I, and that's what we should expect if neural signals take time to do whatever it is that they do - there should be a gap between brain activity and whatever it is that that brain activity is about.
That description just assumes that the mind is the brain and that mental events are brain events.
What is recorded is a brain event.
It is then noted that the participant reports thinking that they formed an intention at a slightly later time than that brain event occurred.
Okay - how does that imply we lack free will? That's what I'm wondering.
Libet saying 'form an intention to raise your hand' is also an event and it is also causally responsible for the subjects forming such an intention. Does that somehow demonstrate that they lack free will? Surely not, as just about everyone would admit. So why does showing that a brain event precedes our intention formation magically show that we lack free will?
What if the brain event 'is' the intention to raise the hand? It isn't - but let's just assume it is.
What would this show? Well, just that we're not very accurate when it comes to judging when, precisely, certain mental events occur. Which again, is hardly surprising (I'd have thought it was virtually inevitable, given I'd have not just to form the intention to flex my hand, but the additional thought "I am forming the intention to flex my hand", with the latter being subsequent to the former) and doesn't imply anything re free will. I thought I formed the desire to X at time t2, in fact I formed the desire to X at time t1. Ok. Why does my mistake imply I lack free will?
We don't have a choice or, more accurately, it doesn't help the case for free will based on dualism for the simple reason that brain activity precedes thoughts and causality as it's understood leaves no room for thoughts causing brain activity which would've been the preferred outcome of Libet's experiment for free will proponents who want to argue from dualism.
An intriguing fact that Libet needs to consider is that in all cases we feel the intent preceding the act i.e. even for the subject in his experiment it must be true, when asked, that the subject will report that, as far as fae was aware, fae first intended to flex faer hand and only then did fae move faer hand.
The experiment's findings contradict the universal experience of intents preceding acts.
Something's wrong. Any ideas?
We could set up an experiment in such a way that the subject tells us when an intent forms and we record when the act intended is performed. I'm certain that in this case intentions will precede the actions intended which is exactly how we feel/know the whole business of intent-action plays out.
Perhaps Libet shouldn't just stop at recording brain activity before the subject offers to reveal that fae has formed an intent but also check what the instrument registers after the subject reports an intent has formed and during the actual act of what was intended. The brain scans or whatever method Libet's using to keep track of brain activity should hold a clue to solving this mystery, no?
Like I say, either they show that our intentions have causes (something we surely don't need any experiment to show us, for it has been known for as long as people have been forming intentions) or they show (on the false assumption that brain events and mental events are identical) that the thought 'I am forming an intention' itself takes a bit of time to form, and thus will represent the intention itself as occurring later than it actually does. Either way, we do not have even the beginning of a proof that we lack free will. And thus those who think otherwise - and engage in any debate over free will and it is only a matter of time before someone raises Libet's experiments - are simply confused.
I must disagree. The point of Libet's little experiment is to demonstrate an, here physical, event that has bearing on free will, happens before the relevant intention forms. This would blow the notion of free will out of the water as there's a causally relevant brain activity that precedes the formation of intent. After all, if my intention to do something is not the first in the chain of events that lead up to my doing that thing then my intention is not the point of origin for not only that particular action but possibly everything else I do. All that sums up to no free will.
Still all very inconclsive.
We know we have survival instincts that trigger reflex built into our physiology, but it's a bit of a stretch to conclude that we lack free will from these experiments.
Here is a more recent experiment.
There appears to be an initial reflex, but will itself can be driven from another part of the brain.
Some key excerpts:
The lower reptilian part of the brain is warming up the ape part of the brain to respond?
The parietal lobe integrates sensory information among various modalities.
You can trigger a convulsion in someone by electrocuting them, doesn't say much about their free will though. I'd be careful to avoid conclusions of the existence of there being no free will in the earlier experiments.
Also, be mindful of the fact that the brain is electrical also. Effects that appear to violate cause so as to suggest we in some way lack free will, are potentially just our misinterpretation and false classification of relativistic effects at play in the brain. It may well be more accurately a relativistic impulse to a local spacetime change in our environment for all we know. This may be how we experience premonitions. We can technically sense the "future" (a change in local entropy) to a degree, due to the invariant speed of light and relativistic rules which our brains too must also adhere too. Time is ultimately illusory.
No. I was just linking to another TPF thread on a similar topic. You are free to draw your own conclusion. :smile:
But that wouldn't blow free will out of the water - it wouldn't touch it. If the point is just that there is a brain event - P - that occurs slightly before the mental event of intention forming - Q - then all it is doing is drawing our attention to something that we all knew already and that didn't need a brain monitor to establish. Namely, that our intentions have causal antecedents. Again, the event of Libet saying 'form the intention to flex your hand' is one of those. It is an event; it causes the formation of the intention (it's not pure coincidence that the subjects formed that intention subsequent to him telling them to form it); and it occurs prior to the formation of the intention.
When it comes to whether we have free will or not, the central issues seem to be whether our mental states trace entirely to external causes, and/or whether the causation in question is deterministic or indeterministic. Those issues are in no way settled - in no way settled - by the Libet experiments. That is, Libet's experiments do not, for instance, somehow show us that incompatibilism is true and that determinism is true (a combination which would indeed entail that we lack free will).
So again, contrary to widespread belief (widespread belief, that is, among non-philosophers - most philosophers are going to agree with me, because they can think straight), Libet's experiments imply precisely nothing about whether we do, or do not, have free will. It is utterly bizarre that so many think they show we lack free will and reflects, I think, just how little thought most people give these issues and how eager they are to accept the judgements of hacks over experts.
Just to reiterate: they don't do anything at all to challenge the idea that we have free will. I mean, absolutely nothing. For instance "there's a tree outside my window". Does that observation challenge the idea that we have free will? No, not in the least. It's just an observation about a tree and its relation to my window.
Well, Libet's observations are relevantly analogous: they don't do anything to challenge the idea that we have free will.
But let's say that they somehow do, becuause - as some seem to think (bizarrely) - they show our conscious decision making processes to be causally inert by-products of brain processes. Okay, well if that's what they show - and they don't - then free will would be undermined for all decisions, no matter how complex.
So I do not see why you think that 'if' they challenge free will they only challenge our free will where simple decisions are concerned. I mean, he could just run the same experiments for extremely complex decisions, presumably. It would just be rather time consuming.
They couldn't even do this experiment without controversy (https://blogs.scientificamerican.com/observations/how-a-flawed-experiment-proved-that-free-will-doesnt-exist/). How are they going to set up an experiment that involves me talking to multiple people, collecting huge amounts of data, and then making a final decision? That's a process that can take months.
But let's say they did and they saw some "readiness potential" before the actual final decision was made. That's OK. I'll just claim 90% of the decision was me consciously counting up the costs/benefits over a matter of weeks, and the final 10% was my subconscious nudging me towards a final decision (the "readiness potential" that the EEG shows). I'm OK with ceding some of my autonomy to my subconscious.
I don't believe free-will is compatible with materialism.
Beside the point. It could be done in principle, and it's implications would be the same. So the idea that his experiments challenge our free will for 'simple' decisions, but not more complex ones is simply baseless.
Quoting RogueAI
This doesn't explain how his experiments challenge one kind of intention and not another. So, I form the intention to flex my wrist. Somehow his experiments are supposed to challenge the free will of that. I form an intention to buy a house. Well, they'd challenge that just as much. And if the latter was preceded by lots of other intention-formings, well, the same would apply to all of those. So I just fail to see on what rational basis one could say 'ah, but more complex intentions are immune".
No, nor me. But his experiment does not show us that materialism is true or do anything to show us that materialism and free will are incompatible. They are incompatible, I think, but nothing in his experiment draws our attention to that.
So the claim is then that a complex decision is a bunch of sub-decisions, which could be monitored for this "readiness potential"? Maybe. It's a good point. I never got into the free-will debate much, so I don't have a lot of background knowledge with which to talk competently on it.
Indeed, I and most people will think of a red tomato. This does prove that there is a limit to my free will. Zebra. You have no choice. Once you read something, you must think of it. However, this does not mean that that you have no free will- only limited free will. If the movement of matter in the brain makes one move, this does not negate Free Will. While a Will is not matter, matter may have a Will.
Even if the vast majority of our behaviors are otherwise predictable, it would be an error to now conclude that there is no Free Will. This is not the current state of the science. We are not able to predict all behaviors in a placebo controlled double-blind experiment, or any experiment. Until all behaviors are accurately predictable, I cannot surmise that there is no Free Will.
My empirical analysis of scientific study on the issue of Free Will, shows that there is a great degree of determinism, but Free Will has not been eliminated. There is a good article on this at http://philosophersunion.org/
Actually no. But even if that is what his experiment did, I did that too: red tomato. Now you're thinking of a red tomato. I knew you would. See?
We - that is, reflective human beings - have always known that decisions have antecedent causes and known that if one knows enough about what those antecedent causes are, one can make reliable predictions about what someone will decide to do. It's not something his experiments showed, and by itself it implies nothing about whether we have free will or not. So the experiment has zero importance to the free will debate. Zero.
My understanding is the test subjects were told they were supposed to move their finger. And they were to pay close attention to a clock, and note when they actually made the decision that it was time to move the finger.
So they went into it with that understanding. Then, they went about it. They thought about moving their finger. Contemplated when the right time would be. Then, finally, moved it.
After all that, I don’t find it very reasonable to say their body, or subconscious, or anything other than their consciousness, made the decision to move their finger. We do things reflexively and unconsciously, but this doesn’t seem to be one of them to me.
I’d be very interested if, while consciously deciding when to move a finger, the person’s body or subconsciousness made the decision for the leg to kick out.