In 1929, Albert Einstein, at that time living in Berlin, gave a wide-ranging interview to George Sylvester Viereck that was published in the Saturday Evening Post. The interviewer seemed like a star-struck teenager and was unduly fawning but nevertheless obtained some interesting quotes from Einstein. One of them (“Imagination is more important than knowledge. Knowledge is limited. Imagination encircles the world.”) was been widely circulated.
Einstein’s views on free will are also interesting.
I am a determinist. As such, I do not believe in free will.
…I believe with Schopenhauer: We can do what we wish, but we can only wish what we must. Practically, I am, nevertheless, compelled to act as if freedom of the will existed. If I wish to live in a civilized community, I must act as if man is a responsible being.
I know that philosophically a murderer is not responsible for his crime; nevertheless I must protect myself from unpleasant contacts. I may consider him guiltless, but I prefer not to take tea with him.
…My own career was undoubtedly determined, not by my own will but my various factors over which I have no control – primarily those mysterious glands in which Nature secretes the very essence of life, our internal secretions.
…I claim credit for nothing. Everything is determined, the beginning as well as the end, by forces over which we have no control. It is determined for the insect as well as for the star. Human beings, vegetables, or cosmic dust, we all dance to a mysterious tune, intoned in the distance by an invisible player.
We see that Einstein was, at least at that time, a hard determinist. In modern terms, this would be stated as us believing that we are purely biological beings shaped entirely by our genes and environment, with no ‘ghost in the machine’ (a formulation by Gilbert Ryle) inhabiting us that is not constrained by our biology and that can tell us what to do. Of course, our lives are affected by any number of what we perceive to be random events that occur in our environment (such as rain falling that causes us to change our travel plans) and can seemingly change the course of our lives. But a hard determinist could argue that even those seemingly random events were determined by prior causal factors. Hence the entire history of the universe was predetermined by the laws of nature and the initial conditions at the beginning of time.
Even though the uncertainty principle formulated by Werner Heisenberg in 1927 introduced an unavoidable element of stochasticity into the workings of physical laws that precluded hard determinism of the kind envisaged by Einstein and others, it was still a new idea in 1929 and we know that Einstein felt that quantum indeterminancy was a consequence of that theory being incomplete and that a more complete theory would eventually be developed that would eliminate it. So he clearly felt comfortable ignoring the element of stochasticity.
A new theory to replace quantum mechanics has not not emerged and we now believe that stochasticity is an inherent part of the working of laws and cannot be ignored. However, accepting its existence does not salvage free will as it is commonly undestood. As Anthony Cashmore says in an article titled The Lucretian swerve: The biological basis of human behavior and the criminal justice system, the existence of stochasticity does not automatically mean that we are responsible for our actions.
[E]ven if the properties of matter are confirmed to be inherently stochastic, although this may remove the bugbear of determinism, it would do little to support the notion of free will: I cannot be held responsible for my genes and my environment; similarly, I can hardly be held responsible for any stochastic process that may influence my behavior!
Cashmore introduces a definition of free will that takes into account this unavoidable stochasticity (S) as well as genes (G) and the environment (E).
I believe that free will is better defined as a belief that there is a component to biological behavior that is something more than the unavoidable consequences of the genetic and environmental history of the individual and the possible stochastic laws of nature.
Cashmore denies the existence of such a component and says that GES is all there is and hence denies the existence of free will, though this denial does not lead to the hard determinism of Einstein because it allows for the uncertainty introduced by stochasticity.
Many people fear that if we deny free will and responsibility for our actions, then how can we punish people for actions that we consider to be wrong? Do we reach a stage where anything goes?
Philosopher Greg Caruso in a debate with Daniel Dennett says that that is not the case. What such a view entails is the elimination of the retributive aspects of justice, that people deserve to be punished for their actions, though other reasons still exist for imposing punishments. It is retributive thinking that leads to excesses such as torture and other forms of extremely harsh punishments as well as the death penalty. Denial of free will would eliminate the rationale for such harsh punishments.
Consider, for example, the various justifications one could give for punishing wrongdoers. One justification, the one that dominates our legal system, is to say that they deserve it. This retributive justification for punishment maintains that punishment of a wrongdoer is justified for the reason that he/she deserves something bad to happen to them just because they have knowingly done wrong. Such a justification is purely backward-looking. For the retributivist, it is the basic desert attached to the criminal’s immoral action alone that provides the justification for punishment. This means that the retributivist position is not reducible to consequentialist considerations that try to maximise good outcomes in the future, nor in justifying punishment does it appeal to wider goods such as the safety of society or the moral improvement of those being punished. I contend that retributive punishment is never justified since agents lack the kind of free will and basic-desert moral responsibility needed to ground it.
While we may be sensitive to reasons, and this may give us the kind of voluntary control you [i.e., Dennett] mention, the particular reasons that move us, along with the psychological predispositions, likes and dislikes, and other constitutive factors that make us who we are, themselves are ultimately the result of factors beyond our control. And this remains true whether those factors include determinism, indeterminism, chance, or luck. This is not to say that there are not other conceptions of responsibility that can be reconciled with determinism, chance or luck. Nor is it to deny that there may be good forward-looking reasons for maintaining certain systems of punishment and reward. For instance, free-will skeptics typically point out that the impositions of sanctions serve purposes other than punishment of the guilty: it can also be justified by its role in incapacitating, rehabilitating and deterring offenders.
Caruso says that we should give up the idea that we deserve whatever rewards and punishments we receive. Rewards and punishments must be based on rationales other than just deserts.
Dennett’s position is one that is called compatibilism. He accepts that we are biological systems with no ghost in the machine but argues that we are deserving of rewards and punishments because we grow up as adults to become autonomous, self-controlling agents. He says that “You weren’t responsible for becoming an autonomous agent, but since you are one, it is entirely appropriate for the rest of us to hold you responsible for your deeds under all but the most dire circumstances.”
I do not quite understand Dennett’s argument. How do we become autonomous agents if the processes of growth are purely driven by the GES factors?
It is hard for people to relinquish the idea that they have free will because the sense that we are making decisions and then carrying them out is so strong. Einstein explained this away by quoting Schopenhauer that that feeling of volition is itself determined: “We can do what we wish, but we can only wish what we must.”
I am firmly with Cashmore and Caruso on this issue in believing that we do not have free will. I have long been interested in this question and back in 2010 wrote a 16-part series of blog posts that looked the history of research into this question and the accumulating evidence that persuaded me to abandon free will despite my initial hesitancy to do so.
My main insight from reading Dennett’s stuff on free will is that «free will» isn’t really a well-defined concept (like, what exactly do you mean when you say «free»?), and so it doesn’t make much sense talking about whether we believe in it or not. Only when you get a bit more precise about what levels of «freeness» you are talking about might you make a similar-sounding question that is answerable. Maybe.
If we can travel into the past, then the past still exists. From the point of view of a person in the past, we come from the future and therefore the future already exists.
I agree with both major positions discussed.
1)Stochasticity does not save “free will” as most people understand it. It is part of the natural system, and clearly what people understand free will to be is something from outside the natural system. For materialists such as you and I and Dennett, free will is the last remnant of dualism they think they have abandoned.
2) We should get rid of retributive punishment. As mentioned, there are other reasons for punishment, such as to protect society from a person who is likely to commit harm again. The present discussion concerns philosophical underpinnings. To which I will add this: It doesn’t work. So there are pragmatic reasons to reform the system.
Another aspect is that we have no access to the process by which we arrive at any choice we make. Our decisions to act happen for the most part in our subconscious mind. It appears that once a decision is made our conscious mind invents a story that justifies said decision. Our consciousness isn’t the CEO it is the press officer.
… free will is better defined as a belief that there is a component to biological behavior that is something more than the unavoidable consequences of the genetic and environmental history of the individual … Cashmore denies the existence of such a component …
Seems to me a lot of these questions bear on the different explanations offered to explain transgenderism: a lot of TG persons seem to express a form of essentialism that challenges material frameworks (If both body and lived experience match a given gender pattern, how can someone “_be_” another gender?). These seemingly abstract, sort-of metaphysical questions crash into the real world in multiple ways beyond crime/punishment scenarios, often putting innocent vulnerable individuals at (further) risk.
My problem with this is, the people using this argument are usually not biologists, and have a very shallow interpretation of what constitutes “the body.” I.e. they look mostly at external genitalia. Can a materialist deny that organization of the brain constitutes part of “the body”?
I am with @1 KetilT. As long as free will is so ill defined we better follow Wittgenstein’s advise:
“Whereof one cannot speak, thereof one must be silent.”
“as most people understand it” hence there is no free will is a terrible argument (I am not accusing RegS of making it, but Jerry Coyne has “argued” something silimal). The question is: can make free will make sense on naturalism? It’s up to neuroscientists to answer it by developing a model of the human brain (and preferably of other animals too). My bet is that it eventually will, but I tend to lose such bets.
If free will is defined as agency, and the ability to manage events to achieve desired outcomes, then humans clearly have free will. I prefer the non-biblical term agency.
The definition offered by Einstein might apply to particle physics, but we aren’t merely particles or machines. Just because you are limited by physical factors and conditions beyond your control doesn’t mean that you are controlled by predetermined outcomes. We routinely make stuff happen, we prevent other things from happening, and have evolved large brains due to many thousands of years of trying to predict the consequences of various actions.
Clearly none of these men have experience with raising children, who have immature brains and actually lack the ability to refrain from doing a forbidden thing once they have thought of said thing. Self control over impulses takes many years, and occasionally letting them suffer some small negative consequences for making poor choices.
Reginald Selkirk @ # 6: Can a materialist deny that organization of the brain constitutes part of “the body”?
No, but that raises a lot of questions about how much of that brain structure came with the DNA and how much derives from (a) environment and (b) “internal” factors (e.g., does mentally rehearsing something over and over “lay a track” in the neurons?).
We have a long way to go before we can pronounce firm conclusions about any of this.
‘free will’ is as absurd a notion as ‘soul’, and both arise from human exceptionalism.
Tathys @8:
We’re very complicated organizations of particles. As such, we are governed by physical laws.
Sorry for the misspelling, Tethys.
If you don’t believe in supernatural, I don’t see how you can believe in free will. Sure we all make decisions but these are all based on physical and chemical processes on the existing molecules in our bodies and environment (another way of saying the same as the GES mentioned in the post). The question of free will then becomes if any decision made could have been different from what it was and that is impossible without breaking natural laws.
The stochastic aspects do not change this but simply prevent the predictability of the decisions.
It’s not, so the rest of your comment is irrelevant.
Really, much of the discussion about free will is taken up by people redefining the terms rather than answering the questions. This includes Dennett.
Rob Grigjanis
We are limited by physical laws, but physics doesn’t effect human agency in making decisions and choices such as ‘What should I make for dinner?’ or ‘What will happen if I decide to use a nail to write my name on my Dads car door?’.
I do agree that the entire concept of free will as a divine gift from supernatural gods is simply inaccurate. We have consciousness of cause and effect despite being built of matter, so Einsteins purely mechanistic physics of matter is not useful to fully explain such emergent traits as consciousness or agency.
It does limit the available choices, but humans are very inventive at making machines that allow us to circumvent those limitations without breaking any laws of physics.
Reginald Selkirk
Which is precisely what defines the opinion of a hard Determinist. Philosophers aren’t immune from pretentious bias.
Agency is intrinsic to making decisions and preforming actions, and is not limited to humans. The added qualifier of ‘independently of prior event or state’ is rather useless. Nothing exists outside of time.
Brittanica’s definition
Or course physics affects what we do and the choices we make. The only other choice is that there is some sort of supernatural action or some sort of duality outside natural laws. The facts that there are emergent traits from our biology does not preclude the facts that this is all based on physics and chemistry.
@16 what Jean said
What if I’m a meat robot programmed to believe I have “free will”? Note that that possibility removes any need for us to have a good definition of “free will” because it’s just a noise the meat robot makes with its mouth.
Same with souls. You can print “I believe I have a soul!” till the cows come home and the meat robot’s argument is as good as a typical christian’s. How can you tell a moral robot from someone who is leading an examined life! The next generation of AI chatbots ought to be as good at apologetics as a typical christian. Sad christians, failing at the apologetics for 2000+ years.
Tethys @14:
It’s certainly not very useful to describe chemistry or biology in terms of the underlying interactions between fundamental particles, but the former arise necessarily from the latter. That’s what ’emergent’ means. It doesn’t imply some mysterious additional ingredient which leads to ‘consciousness’, ‘free will’, or ‘agency’. Or ‘soul’.
If it’s not ‘purely mechanistic’, what is the non-mechanistic part?
My main insight from reading Dennett’s stuff on free will is that «free will» isn’t really a well-defined concept (like, what exactly do you mean when you say «free»?), and so it doesn’t make much sense talking about whether we believe in it or not.
I felt that Dennett’s approach was to obfuscate people’s typical interpretation of “free will” then argue that “free will is really complicated.” Well, yeah, you just did a pretty good job of complicating it (to the point where Dennett
says something like “the free will you think you have is probably not the free will you may actually have” it was around there that I concluded I was dealing with a bullshitter. Hey, you too can have ten million dollars if by “ten million dollars” we mean a dime.
Dennett was not dealing with popular conceptions of “free will” in good faith, he was muddying the waters so he could clarify them
-- by stopping muddying them.
Further to my #19: Britannica’s definition
The bolded part is a pretty good definition of ‘supernatural’.
@Rob #19
The experiencing of the first-person perspective through time. Why am “I” experiencing this body/mind over time? Why is anything? Things would make a lot more sense if there was no “I”, just a whole lot of automata. Of course without an “I” the universe would be unchanged: this body/mind that “I” am currently experiencing would continue to think and to write these words, but why do “I” have to experience this animal’s life? Sometimes this body/mind thinks the universe is all a simulation for that “I”.
To clarify, when I write “I” I am talking about the experiencing observer of my life, not the body/mind I am, that’s why I have to quote it. When I write I (unquoted), I am talking about the union of that experiencing observer and the body/mind I’m in. The best term for “experiencing observer” seems to be “soul”, but although the regular I I (sic) use conflates that with my mind/body, the “soul” I’m talking about is nothing (not something that can think or remember) but the link to the continuity of the body/mind’s life over time, not the notion of an incorporeal ghost in popular culture.
You asked and this one was compelled to respond because there is no free will. Of course if you had written something else I would have thought, and probably responded, differently, because my actions are deterministic, but being based on everything I am and have ever experienced its a rather complex function.
file thirteen @22:
In contrast, my husband believes that self-understanding and self-observation can be used to develop a form of ‘free will’ (probably closer to a ‘free won’t’) whereby one learns to identify one’s response as it arises and to question it, its necessity, the motivation behind it, its possible outcomes etc and be very selective in responding, or even come up with a completely different response than the one that arose initially. So in his view ‘free will’ is a kind of talent or ability that people can obtain with a lot of practice, it is not a given that all humans have. (And how do people decide to engage in the practices that will develop this ability? Probably the outcome of an interaction between their personality and the circumstances of their lives.)
So, let’s get reductive. Unless my mother’s egg and father’s sperm carried the mechanism of free will, and in their union it emerged, where did it come from? I did not choose to be conceived. I didn’t choose to be born, and I didn’t choose what I was fed or experienced for the first decade of my life. I was a sponge for knowledge and experiences. Tethys even gave it away in his last paragraph in #8. The experiences of living and learning, especially in the first few years, are the building of self-awareness which includes the illusion of free will. Newborns are not self-aware; it takes years for them to become so.
I think we can drop the ‘S’, it’s determinism all the way down. If there is a mechanism for processing a quantum event built into our DNA, where is it? What is the protein machinery that does that work and when did it first evolve? If it exists it must have been around for a long time for it to be so well adapted and thus be available and used by other mammals if not all vertebrates. How would it even work? Are these quantum detector proteins in every cell, only brain cells, only synapses; and do they detect a photon or an electron going through some quantum change? How do they tell if this change qualifies as a random quantum effect? Does a random decision go on hold until the quantum detector protein gets a hit? This is all absurdity. There can be no such mechanism because biology is chemistry not quantum physics.
Self-awareness is evolved and has evolved several times in other species. Ours is just more complex and probably includes many components unavailable to those other species, but do wolves pause to ponder how best to separate that calf from the rest of the herd or that chimp stop before grabbing a stick to probe for a grub? That stopping to think is just a pause to let the enormous capacity of our previous experiences determine that we can do no other.
Surely this is internally contradictory. The idea of a deterrent presupposes free will. How can you deter a person who has no choice?
@ 5 Pierce R. Butler
Not sure what free will has to do with the etiology of gender variance 🙂 but to address the parenthetical question, you might as well ask how a person with a body labelled “female” and who has only had sex with men can possibly be a lesbian. By experiencing primarily or exclusively attraction to women, that’s how. A lesbian in the closet is still a lesbian.
Likewise, a trans man, assigned female and raised a girl, is still a man by virtue of experiencing much greater comfort and wellbeing with a masculinized body and being seen and treated as a man. A trans person in the closet is still trans.
As for “essentialism”, I think that word means more than simply “innate”. Unless you consider the scientific consensus that left-handedness has a biological basis to be “essentialism”.
@ 21 Rob Grigjanis
What? It’s a “definition” of indeterminacy. Unless you consider a double-slit experiment to be supernatural. No matter how much you know about prior events or the present state of the universe, it is impossible to predict at what point a given photon will impact the screen behind the double-slit. There is a fundamental randomness. The outcome is therefore independent of any specific set of prior events or universe state. Not all possible states of course -- the universe must be such that a double-slit experiment is possible -- but not dependent on any specific state.
Personally, I find discussions about free will rather pointless. It’s unfalsifiable. If we cannot distinguish between a universe with free will and one without, what does it even mean to say free will doesn’t exist? If two things cannot be distinguished by any measurement or test, how can they be said to be different?
“Practically, I am, nevertheless, compelled to act as if freedom of the will existed.”
The practical aspect is the only necessary consideration, the rest is at best a niche area of interest resulting in no difference to the practical necessities, or at worst pointless navel-gazing and pontificating by the supercilious.
Heh.
If there is no free will, then nobody bears blame for anything they do.
But then, that means that those who blame somebody are not to blame for blaming.
Next:
+ Fate and Destiny: are they real?
+ Are we living in a Simulation?
Coming soon.
Silentbob @25:
The probability that a particle hits a particular detector in the double slit experiment depends on the wave function between source and detectors; in other words, it depends on a prior state.
@SilentBob #25
No, a deterrent does not presuppose free will at all. The choice was there, it’s just that (for example) a SilentBob is going to deterministically think and act in a situation according to the way a SilentBob must think and act given the situation, this including any pondering, fretting, vacillating or pretending that they had a choice about it.
It’s not just a function of what SilentBob is, it’s also a function of the environment that the SilentBob is in when presented with that choice, and a deterrent is part of that environment. The SilentBob will do what a SilentBob must do, but that doesn’t at all mean deterrents are ineffective.
Silentbob @#25,
To follow up on what file thirteen said in #30, since our choices are a function of the genes (G), environment (E), and stochasticity, (E), then someone who lives in a society in which bad actions are punished will make different choices from that in which bad actions are not. That is how deterrence works without free will, by changing E.
Silentbob @#26,
There is experimental evidence that indicates that there is no free will. These experiments would have had different outcomes if there was free will. Hence the two universes are distinguishable and, I would argue based on the preponderance of that evidence, have been distinguished.
The fact that the conclusions have not been universally accepted does not mean that the two universes are not distinguishable. It only means that those people are living in one universe while thinking they live in another.
Holms @#27,
As both Cashmore and Caruso argue, there are practical consequences based on whether our rewards and punishments systems are based on beliefs about free will. Free free will skeptics argue that removing the retributive aspects of justice would lead to a more humane system.
Whyever would anyone need to argue that on the basis of free will?
Pointless discussion, anyway.
What one side claims is retributive the other claims is deterrent.
Gah, no. Not accurate….
If that were so, you would have to claim that the thing “we now believe” (where “we” refers to most physicists or philosophers of physics, not somebody like me) is an objective collapse theory like the one from Ghirardi-Rimini-Weber (GRW), which is simply not what most of them believe, unless they’ve been trying very hard to hide that fact from the rest of us for many decades.
GRW may be wrong (I think so), but at least then you would have a genuine physical theory, which does actually say “collapse” is a real physical process that is in fact stochastic. It specifies how that works, which it does by modifying the equations (the ones you’re taking for granted here, so that just can’t be right). In that case, it’s not just a useful fiction or whatever — that’s really what is happening according to the theory, it tells you so, and it is completely open about that.
If instead the idea were something like Many Worlds or DeBroglie-Bohm, that is not the sort of thing that you believe about the world. Those are both deterministic theories, and together they are a lot more popular (and I would say less ugly and less ad hoc) than GRW or its relatives, even if they’re still in the minority.
If you don’t have a GRW-type theory but you do have “collapse” as part of your story, where stochasticity is supposed to enter the picture somehow, and you do this while thinking that you agree with “Copenhagen” or “whatever it is they told me in the standard textbooks” or something to that effect, then what you’ve got is not a genuine, fleshed-out, physical theory at all. It ought to be, at the very least, something that’s an attempt to say something about the real world, not just a way to avoid answering questions about it that you’ve decided aren’t “interesting” enough to deserve an answer. In this case, what you do have is (presumably) some math on the one hand which is generally not the problematic part, together with an incoherent/vague string of words that don’t consistently hang together to mean anything in particular. Even if that is what most physicists happen to think, despite the other options on the table, it’s not enough for a theory of fundamental physics. (It also certainly wouldn’t be a way to refute determinism, if that were your more immediate goal.)
Strange…. It’s not just the conditions “at the beginning of time.” You can take any conditions, at any time, together with the laws of physics, and that will do the job. So it can just as well be conditions a million years in the future. It really makes no difference, but of course we just happen not to know what those conditions are or will be. Obviously, we also don’t know the exact state at the big bang or at any other time. In any case, though, our knowledge about that stuff has nothing at all to do with it.
But for convenience, take the conditions here and now, and then try to stress how weird it supposedly seems that events here and now are determined by those conditions (and the laws). It doesn’t seem quite as weird anymore, does it? So why argue it like that?
#33 Mano
But retributive punishment is not a necessary outcome of taking the position that there is free will; one can have that position and yet judge some forms of punishment excessive.
cr @35:
For the umpteenth time: There are technical senses in which these are deterministic, but what they tell us about the world (the actual numbers we calculate) is inherently probabilistic.
In MW, the wave function is determined. But actual physical outcomes (the spin of a particle, etc) can only be assigned probabilities.
In DeB-B, positions of particles are determined. But you can only know a final position if the initial position is known. And all we can do is specify initial probability distributions, which in turn yield probabilistic outcomes.
To sum up: All we can concretely say about the world (i.e. predicting outcomes, the final state of measuring apparatus) is inherently probabilistic, even if you’ve been overly impressed by the word ‘deterministic’ in various articles.
“You can’t help criming and I can’t help locking you up for it. Them’s the breaks.”
If we can reject the idea of “free will” but wind up living the same way as before, did it matter? I’m programmed to attribute agency to creatures, and I respond according to my programming.
Btw, let me digress briefly: “free will” is very anthropromotional. Anyone who has had a dog or horse will have experience in non-human “free will”/agency. Other primates clearly think and plan the effects of their actions, including using tools. Cats are another question. But if humans have “free will” and certain animals have “free will” that is indistinguishable, what makes us special? One of my dogs once grabbed a steak off the cutting board and I was able to tell right away who it was (“who”) because it was the one who looked guilty.
I’m comfortable that we are meat robots and I’m mostly happy with the survival package this one is running. I wish I had the rock ‘n roll mod but it may work against survival.
To sum up: All we can concretely say about the world (i.e. predicting outcomes, the final state of measuring apparatus) is inherently probabilistic, even if you’ve been overly impressed by the word ‘deterministic’ in various articles.
I know it always comes up but non-determinism just means that the meat robot sometimes rolls 2d20 on the “what do I want for lunch?” table. Like all NPCs in games we are designed to act as though we are player characters.
Holms @#37,
It is true that it is not a necessary outcome. People can argue against excessive punishments without abandoning the idea of free will. In fact, people do it all the time right now.
The point is that abandoning the idea that we have free will removes the current rationale often heard for such punishments, such as “They deserve to be punished heavily for their crimes”. In other words, it is retributive. Some people may suggest forward-looking reasons such as that such punishments act as a deterrent to future crimes but that is an empirical question and the studies so far seem to argue that the death penalty (say) does not work as a deterrent.
Mano @41,
“the studies so far seem to argue that the death penalty (say) does not work as a deterrent.”
.
It is however, extremely effective in reducing recidivism.
txpiper @#44,
If your goal is to reduce recidivism, why not enforce the death penalty for all crimes?
Mano,
“why not enforce the death penalty for all crimes?”
.
I think in terms of impact on victims, so it is a matter of degree. A stolen bicycle and a murdered child call for different levels of legal vengeance. The bike can be restored. The child cannot.
#41 Mano
As you see, the ‘retributive punishment’ types don’t much care for any reasoning which would block their bloodlust.
txpiper @#42&44, Mano @#43:
Of course, the issue with the death penalty is that it also cannot be undone. The life of someone who was wrongly convicted and sentenced to death cannot be restored either.
As long as the court system does not have perfect knowledge, you can’t talk about the impact on the victims without considering the possibility that the accused might be a victim as well.
I tend to take a practical approach to the question of “free will:” even if the Universe is 100.0000000% deterministic and ruled by nothing but physical laws, all the way down to every single particle and photon (including the ones in everyone’s brains), that would not make anything more complex than basic chemical reactions or planetary orbits even 50% predictable to us or any other sentient corporeal being. Even simple human interactions cannot be predicted with deterministic certainty, without gathering enormous amounts of detailed information about: the setting and circumstances; the physical attributes of all persons involved; and the knowledge, experiences and mindsets of all persons involved. (And by the time anyone anyone actually got all that information, processed it, and made a prediction, the actions predicted would have already happened.) So, for all practical purposes, we can claim that we have a considerable amount of free will, without having to talk about “souls” or other supernatural rubbish, and without even having to define exactly what “free will” is.
An argument in favor of there being no free will seems to be that otherwise intelligent people on the Internet seem compelled to repeat and respond to the same arguments 🙂
(Resists urge to ask for the details of the physical laws that govern our decisions, fails)
As for changing the law, here’s what Germany did in the 1950s and 1960s, commonly known as the Great Criminal Justice Reform:
https://de-m-wikipedia-org.translate.goog/wiki/Gro%C3%9Fe_Strafrechtsreform?_x_tr_sl=auto&_x_tr_tl=en&_x_tr_hl=en&_x_tr_pto=wapp#:~:text=Unter%20der%20Gro%C3%9Fen%20Strafrechtsreform%20versteht,der%20Bundesrepublik%20Deutschland%20betrieben%20wurde.
Rob Grigjanis, #38:
Determinism isn’t about what we human beings are able to know (or what “we can concretely say”). The core claims here are about metaphysics, not restricted to epistemology only as it seems you want them to be. You’re evidently confused about that (still), if you thought that all you have to do is tell me (something I already knew) that they have to calculate probabilities in those theories just as they do in more orthodox versions of quantum mechanics. That’s not what this is about. There’s a type of claim that you’re failing to recognize or understand, which is about what’s going on in the world, independently of considerations about our knowledge, our procedures for gathering information, or anything along those lines….
According to de Broglie-Bohm, for instance, it’s not too hard to paint a picture and just visualize what it means to say that the theory is deterministic. The path through the 3n-dimensional configuration space is a single curve, which doesn’t split into multiple component parts (corresponding to different possible configurations), and no two hypothetical trajectories with different configurations at some time would intersect each other, thus having the same configuration, at any other times. (They may be extremely close somewhere, perhaps, but not the same.) I suppose if conditions were just right, things could still be sort of weird in some ways, with closed timelike curves and whatnot, but otherwise it’s pretty simple.
Notice that I didn’t have to say a word about predicting or measuring or observing or calculating or what have you. Because we could just as well be talking about universes which do not have any living/semi-intelligent beings like humans. Those could likewise be deterministic or indeterministic, so maybe it would help if you try to think about how you could even get started on describing ones like that. Or if you really believe that one absolutely must involve scientists measuring stuff with an apparatus, then it sounds like you’re in pretty bad shape, and I just don’t know what else to say.
Anyway, it’s just a substantially different claim about the world (not merely us or our abilities), even though your calculations of the probabilities of various experimental outcomes would completely agree, if you say that there is that sort of branching or that there is not a single determinate history of the kind that I described above, because (according to your theory) objectively speaking there are stochastic processes, not just things/events about which we happen to be ignorant.
That is in fact describing another kind of world that works differently at a fundamental level, according to different types of rules, and philosophers happen to have a (peculiar) word for it. If you don’t like that word or want to talk about something else, okay…. But as it’s ordinarily summarized in plain English, with conditions at any given time and the laws describing their evolution over time, then determinism implies a single definite/determinate history of the universe. If it’s not like that, then the world is instead indeterministic. Pretty straightforward, I think.
Does any of this matter for free will? No, I don’t think it matters even a little bit. But it does come up every single time anyway.
cr @50:
‘plain English’ can be very unplain when you look closer.
In MW, the ‘universe’ which has a ‘single’ definite/determinate history is actually an infinite number of universes. That’s a very different picture from the DeB-B one, in which there is only one universe. So you can claim the same ‘plain’ meaning of ‘determinism’ only by varying the meaning of ‘universe’. Oh yes, very straightforward.
The word games armchair philosophers play…
Every mathematical system will have some statements that can never be proven. Does that make Gödel an armchair philosopher?
Uncertainty is built in to the system. It is both determinate and indeterminate at the same time, which is why “do humans have free will?” is an unanswerable question. Yes, yes, no, maybe? All positions are probable and unprovable.
https://www.quantamagazine.org/how-godels-incompleteness-theorems-work-20200714/
Uh, yeah. Duh. That’s why they’re different theories, and both are different from other quantum theories, the sameness of their empirical predictions notwithstanding. That doesn’t make your #38 any better, of course, since it’s based on that irrelevant stuff which doesn’t answer the determinism vs. indeterminism question, which was the question at hand.
No, I don’t think Many Worlds is straightforward in a lot of ways. And I don’t think it should be branded as a “local” theory, as some have claimed, since that doesn’t make sense at all to me. Maybe that’s just me.
I don’t mind if you want to criticize MW for the determinism stuff, although it seems like kind of a petty grievance, but the locality business is importantly different from the determinism issue, since it can at least be seen in that way, if you squint at it properly, without contradiction. As you said, all you have to do is think about the whole shebang with all of the universes in it, rather than about this particular one. Not so bad, even if you wouldn’t be motivated to do such a thing by anything outside of the theory itself (which maybe feels a little uncomfortable).
In contrast, I just don’t think there is any coherent sense in which MW is “local,” what with the many worlds and all, which are not (presumably) in the same spacetime, and because branching (presumably) is a global/nonlocal thing which occurs for entire worlds as a whole whenever they do that to themselves. Or, it’s just not even clear what the hell those people are talking about, if they even know. So it could mean a lot of different things to different people, I suppose, maybe even to the same people on different days of the week….
Anyway, I was referring to determinism in general. You acted like it had to do with some arcane secrets that were too technical for us non-physicist peasants to ever understand — so why bother even saying anything about it, when you could spend no effort by just rejecting whatever I say out of hand? But I think it’s really not that difficult to explain what the general idea of it is, in just a few sentences.
It’s their word, and you just had the wrong idea about it that was misleading, which is not the end of the world. (It’s odd that you think you had to correct me on it, while also implying that I was technically correct, but whatever….) If you don’t want to talk about philosophy because you don’t like these “games” of theirs, in which you dislike the way they use their own terminology, maybe just don’t weigh on it next time, eh?
cr @53. It’s hilarious how you simply dismiss things that don’t fit into your simplistic picture as “that irrelevant stuff”. That the determinism in MW is radically different from that in DeB-B is highly relevant. In DeB-B, the future in the universe (you know, that thing which you perceive yourself as living in) is completely determined*. That is certainly not the case in MW. So now do you come back with “the universe I perceive myself as living in is irrelevant”?
It’s a local theory in the sense used by Einstein, and by Bell in his 1964 paper; that the result of an experiment at one location does not depend on the settings of an experiment done at a distant (spacelike separated) location. This is true for MW, but not for DeB-B. I suppose you could come up with your own definition of ‘local’ if you like.
Please tell me where I “acted” like that. I’m pretty sure what I wrote would be clear enough to most people who can read.
Yes, they are in the same spacetime. The branching is in configuration space. And branching is not globally instantaneous; it is contained in the future light come of the splitting event. I’m sure we’ve covered this in the past. You could find out yourself with a little digging.
*Actually, that may not be true. Some attempts to formulate a BM version of quantum field theory require particle creation and annihilation to be inherently stochastic. Others are beavering away trying to keep things deterministic. And still no realistic theory (like quantum electrodynamics) anywhere in sight.
cr @53:
I’m not talking about the serious practitioners; they would understand the sense in which the determinism of MW (the wave function is determined) radically differs from that of DeB-B (positions are determined). And I’ve come across many lay folk who have a fair grasp of this, having taken the time to read and ask questions.
The irrelevant part had to do with calculating probabilities of various empirical phenomena, which literally any conceivable theory can do whether deterministic or not. Giving predictions in that form, or giving the same predictions as some other theory of whatever kind, simply does not indicate whether or not a theory says the world is deterministic. This isn’t at all to say empirical results “don’t matter” or some such thing, but this can’t be the way you have to go about answering that particular question.
I have no interest in defending MW. I do think it meets the (extremely minimal) requirement that it can be consistently described as deterministic, and you yourself already said as much in your first response. That claim just doesn’t say all that much about it, although it does say something, and of course it doesn’t mean the same thing in a theory like MW as it does in one like dBB … or Newtonian mechanics,* relativity or whatever other physical theories you want to consider.
*Which, as you may know, has its own issues with determinism, in some very exotic edges cases that aren’t of any practical concern in the real world (as far as anybody can tell or as far as we care). This, despite it being the sort of paradigmatic case of a deterministic theory against which others are typically compared, for better or worse. So, alright, if you want to pick away at the idea that this stuff is “straightforward,” then fine, be my guest. It can get sort of hairy.
Bell’s theorem assumes (without argument) that we’ve got a definite experimental outcome in one universe (not all of the different outcomes, which are thought to occur in different worlds), so that by itself couldn’t prove anything about MW either way.
I think you can give other arguments why it should be considered nonlocal. We’ve already done lots of experiments that show nonlocality (in Bell’s sense) empirically. At least if we leave MW to the side, there aren’t ever going to be any theories that can correctly predict those phenomena (that we’ve definitely already seen) which are nonetheless local somehow. And I just don’t see how MW would change that, at least not in a way that would make any difference to anybody who wants to understand how QM could fit comfortably with relativity.
If that’s what some of them say, alright. It seems odd that the very same spacetime isn’t affected at all (presumably) by countless alternative versions of material objects being in multiple locations at the same time. If there were such an effect, then isn’t that something that could be observed, in principle? And if there were not, why not? I was told spacetime and matter/energy are dynamically related, and it seems like that story shouldn’t be any different here.
If it’s in configuration space (which has 3n spatial dimensions), then it’s kind of strange to say it’s contained in a future light cone that is in spacetime (which has 3+1 dimensions). You should have to pick one or the other and stick with it.
I know they’ll say something like configuration space (or Sean Carroll has said Hilbert space) is the real space and there isn’t really matter in spacetime, just the wavefunction. What would that be a configuration of? Not clear either. But that’s the idea, despite any appearances to the contrary and the actual evidence we’ve got which consists entirely of matter being somewhere in spacetime.
Anyway, as I already said, we see nonlocality experimentally. All of those results indicate that it is instantaneous, in spacetime (i.e., subsystems A and B, in spacetime, at spacelike separation, are nonlocally correlated, as Bell said). If MW predicted instead that it takes some time for this to occur with A and B, then it would just be making the wrong predictions about them, which would be no good. But it doesn’t make the wrong predictions about those experiments.
So whatever they might want to say about the story from the view of configuration space or Hilbert space or whatever, you still have the same nonlocality in spacetime that everyone is actually interested in, since for one thing it points to the tension between QM and relativity which is of major theoretical interest.
Does that sound about right to you, or am I missing something? Maybe there’s a sleight of hand kind of parlor trick you can do mathematically, to avoid “nonlocality” in some abstract space, but that’s not an especially useful or interesting or enlightening thing to do as far as I’m concerned.
In #38: “There are technical senses in which these are deterministic” — that’s it, but not a word to cash that out and say what it’s supposed to mean. It’s just “technical,” so I was only technically correct, which of course is the best kind of correct.
Maybe you didn’t mean it that way, and it’s no big deal. But it does seem sometimes like you don’t need to explain yourself nearly as much as you expect from me or others. (And when I try to do that, like in this comment, it becomes exceedingly long, which is also a source of complaints. Sorry about that, by the way.)
John Morales @34:
Deterrence can be measured empirically. Or at least, the success of deterrence can be measured. And we know from such measurements that what matters is certainty of consequences, a lot more than severity of consequences.
anat, if you really think that’s what truly matters, it follows that if there were (say) a 100% conviction rate for murder though the penalty were only a $1 fine, you believe that the maximum possible deterrence of murder would be the result.
I disagree.
Well, not a $1 fine, but a not-very-long imprisonment (I do not remember the exact comparison, I read it a long time ago) with high certainty works better than life imprisonment or the death penalty with low certainty.
I’m quite familiar with the research, anat.
It is true that, ceteris paribus, likelihood of enforcement is a more effective deterrent than degree of punishment.
But this observation is more in relation to petty crime such as shoplifting than more serious crime, and hardly applicable to crimes of passion or derangement, for they are not things done on a basis of cost-benefit.
Point being, I see no real basis where the concept of ‘free will’ (which is much more relevant in a religious milieu where the problem of evil is evident yte excused via that concept) is either necessary or sufficient to argue for less retribution and more pragmatism in the so-called ‘justice system’.
That noted, there is an idiom that’s most applicable to overly-punitive circumstances: “one might as well be hanged for a sheep as a lamb”.
Clearly, even popular consciousness has long understood that increasing the severity of punishment is a matter of diminishing returns, at best, and that it has a cut-off point, and that beyond that point it actually has negative utility.
cr @56: Skipping over some points we’ve gone over in the past; if my comments on those had no impact on you then, I’m not wasting my time repeating myself.
Doesn’t matter. The locality condition doesn’t care about multiple universes. You can add ‘in a particular universe’ to the start if you want.
No, that’s not “what some of them say”. That’s what the Schroedinger equation (SE) (or its relativistic generalization) says. To accommodate different spacetimes, the SE would have to be modified for each such splitting, with the size of the configuration space being multiplied for each branching. But the MWI simply says (note: I’m not advocating, just describing) that for an N-particle universe, the wave function is a function of 3N spatial coordinates, plus time (ignoring things like spin for simplicity) evolving according to the SE.
I think you know that a single-particle wave function can in general be written as a superposition of states in some basis (analogous to the x,y,z components of a 3D vector). Asking why different worlds don’t interact is akin to asking why the different components of a single-particle wave function (in some basis) don’t interact with each other. A more detailed answer for MW would involve things like entanglement, decoherence, and so on, and is far from completely understood, as you have pointed out.
Some region of the configuration space would represent a subset (say, n) of the N particles being very close to a particular 3D location x,y,z. One of those n particles is an electron, and the n−1 others are a spin-measuring apparatus, maybe a person, etc. If the measurement* is made at time t, the light cone is the one associated with spacetime location (x,y,z,t). Not that complicated.
The following sentences in that comment explained “what it’s supposed to mean”.
*And, of course, it doesn’t have to be an actual experiment in a lab. It could just be some interaction between a one-particle state and an (n−1)-particle state near a particular spacetime point.
Rob Grigjanis, #62:
I don’t get it. And I wasn’t planning on adding anything to it. Are you saying Bell’s theorem proves that MW is local?? (You’re definitely claiming elsewhere that it’s local, so you apparently don’t think that it proves nonlocality for MW.)
I was saying it doesn’t by itself prove either and just wanted to be sure we were on the same page about it. I guess we’re not. Or if you think that is correct, but you think something “doesn’t matter,” I just don’t know what you’re trying to say.
Sure. I know you’re not really advocating for it, but if they’re going to insist that spacetime somehow emerges from a different space which is really the fundamental one, they ought to tell the whole story in those terms, in my opinion. Make them work for it, you know? It’s not an objection that breaks theory or whatever, just a petty grievance and me being a little too irritable maybe.
Anyway, that’s not the argument about nonlocality (which also doesn’t break it, BTW), which I notice you didn’t touch. I’ll try to make this relatively short and hopefully clear…. If A and B are entangled and spacelike separated, and A for instance could be spin up or spin down (meaning you get different branches and can make whole new worlds with this very minimalistic setup), then we know the branching isn’t something that propagates through spacetime at the speed of light or less (or is contained in a light cone).
Maybe some hope that decoherence or some such would offer that somehow, but people have been doing these kinds of experiments for decades and those experiments don’t support that. It does not take that time for some kind of signal to travel (arbitrarily far) from A to B and tell B that B’s up/down state should be in one branch or in the other branch. Because (1) there just is no such thing in what we see empirically, and (2) that is not what you would get from the standard predictions that MW is supposed to agree with completely, as far as I understand it. If they disagree with that, they’d have to disagree with those experiments, which looks like a lost cause.
That’s why I say it’s nonlocal, since locality isn’t really an option even in this case, although some may not be too enthusiastic about advertising that I guess. It doesn’t look like there’s any way out of that, which isn’t so bad since that just puts it in the same boat as the others. I think you can just get used to it, even if it’s weird.
Barely….
“In MW, the wave function is determined.”
“In DeB-B, positions of particles are determined.”
So then, you’re saying that determinism means things are determined (who could’ve guessed?), and since different theories stipulate that there are different things, which things are so determined depends on the theory in question. Still nothing clear about what it amounts to for something to be determined, though. It is at least a way that things can be (or not be), whatever that might be about.
I mean, yeah, this is fine as far as it goes, but it’s not exactly informative.
cr @63:
Nonsense. Please provide evidence/links/references that “we know” this.
This is one of those topics I mentioned at the start of #62, which we have batted about before. The last time I recall, you had no response for my final comment. Maybe you were bored, or distracted. Either way, I have no desire to repeat myself for no good reason. It’s not a simple subject, and it’s really not worth my effort.
You really don’t know what I’m referring to, or are you just dragging this out? I would be completely stunned if you didn’t already know about at least one of these.
If you want to explain clearly why none of that matters (for MW specifically, I suppose) and why none of those people really knew what they were doing when they were closing loopholes and so forth, then go right ahead.
cr @65: You’ve demonstrated yet again that you don’t understand the stuff you quote. What fails is local realism. That means you can’t have both locality (the local part) and hidden variables (the realism part). You can only have one or the other.
I know this because I read Bell’s bloody paper decades ago.
Rob:
Look, if you think “local” means “local,” I get it. That is what it means. Nobody should have any trouble with that.
But “realism” doesn’t mean “hidden variables,” and you (along with everybody else I’ve ever heard who says this junk) provide no good reason to think so.
It doesn’t just go without saying, like the example above. You don’t just get to pound the table and say that I’m dumb, as if that demonstrates anything. If you’re tired of this and want to walk away, fine. Neither of us thinks MW is right anyway, so it hardly matters. But remember next time that you never did actually argue for it, explain where you get this stuff, or how another person who’s not you could come to understand whatever you think I don’t understand … while I have been giving reasons and trying to explain myself.
The EPR sense in which there are “elements of reality” (that correspond to quantities you can predict without disturbing a system) may have suggested to Einstein that there were so-called “hidden variables”, since QM at the time wasn’t making sense of it given an assumption of locality.
And there may be such things, if something like dBB is right and you want to call particles the things that are hidden (and not the quantum state). More dumb terminology for you…. Anyway, that is an option here, but that’s not what realism itself is. It’s not the definition of the term, nor is that what Einstein or Bell would have meant by it. This just comes from a strained attempt to argue that the “problem” is only over there, with some other theory that you don’t think is right and don’t have to think about.
What Bell showed is that Einstein couldn’t have locality, which is what he obviously wanted and what he assumed could be done somehow with a more complete theory. But it’s just absurd to think that somehow it could proven that it’s alright to have a “non-realistic theory,” which people are actually supposed to take seriously. Bell would not have taken that seriously and didn’t prove that. You may as well say you’re just not doing physics at that point, because you don’t care what’s real or not real. Not Bell’s style at all, if you’ve read anything of his other than that one “bloody paper” a long time ago.
When you can predict what’s going to happen to a system (by doing something which Einstein incorrectly thought wouldn’t disturb it, since it was too distant but leave out the “incorrectly” part if you like), then what kind of bizarre theory would you need, to say that nothing real is associated with that? Certainly not one that merely lacks “hidden variables,” but not even one that ought to be described as physics. You’d just be predicting stuff like fucking Nostradamus which isn’t based on anything whatsoever, and whatever you want to call that, it’s not physics. Do these “elements of reality” sound to you like the kind of thing you could just reject and still have something that makes any sense?
Also, when you don’t have such elements of reality, then what the hell could you even mean by the statement that the non-real stuff you’re making predictions about are “local”? You might as well claim that unicorns and leprechauns are local, while also insisting that they’re not real. At best, it’s just a vacuous claim, and at worst, pure nonsense.
If you’ve got a different way to handle this stuff, that’s not “hidden variable” (in dBB, particles), then great. There are theories like that. But it’s not like anything goes as long as you avoid those treacherous hidden variables, nor is it like those experiments are irrelevant to everything else…. What would even be the point of them for non-Bohmians? Why do you think those people would bother doing them like that, decade after decade, very meticulously and expensively for that matter? What’s all the fuss supposed to be about? Am I the only one who just doesn’t get it like you do, or is it also a bunch of working physicists and philosophers who don’t agree with you about this (despite the fact that you read a paper years ago)?
@Rob #66:
I presume you meant no hidden variables?
file thirteen @68: No. In this context, realism refers to the notion that a given state, even before any measurement is made, has certain properties (e.g. position and/or spin) that have definite values. In quantum mechanics, if you want to claim that a particle always has a definite location even before you measure position (“position realism”, if you like), you have to treat position as a hidden variable. In other words, you have to add something to “bare” quantum mechanics.
I gather the term ‘realism’ has fallen out of fashion somewhat, having been (more or less) replaced by ‘counterfactual definiteness‘. But I’m an old fart, and a lazy typist.
cr @67: I asked for something which showed that “we know the branching isn’t something that propagates through spacetime at the speed of light or less (or is contained in a light cone).”
The link you provided does nothing of the sort. Wanna try again, or do we just get more semi-coherent rambling?
Rob Grigjanis @ 69
But isn’t uncertainty what needs to be added to account for hidden variables? It’s averages and probabilities, so the value given to uncertainty can account for any statistical outliers without having to calculate them precisely.
Tethys @71: Uncertainty is inherent to quantum mechanics. It doesn’t have to be added.
To be more explicit: even in a theory in which the position (say) is a hidden variable, all we can know about the position (and momentum) is contained in the wave function, from which we derive the uncertainty principle.
@Rob
Ok, but the indeterminacy is still fundamental to the equation. It’s inherent to any probability distribution.
Quoted from wiki
So indeterminacy is a fundamental value of the quantum wave state, which also has stochastic and determinist states as fundamental values.
Tethys @74: Sorry, I don’t get your point. Can you give a specific example of a quantum wave state (I assume you mean a wave function), and the “stochastic and determinist states” associated with it?
@Rob #69:
Well this particular armchair philosopher isn’t following then. That was a deperate attempt of me to understand the conversation.
What I thought you were talking about (I only put in this paragraph for clarity of my thought process, so feel free to skip it) was entanglement, such that two separate but entangled particles either had to be “local”, meaning to me part of a common element in a deeper reality than we see so that any measurement of one’s value is in fact a measurement of the pair and that “measurement” doesn’t have to propagate through normal space from one particle to the other which would otherwise have to be constrained by the speed of light, or must have “hidden variables”, meaning that the entangled particles have identical values in a property we haven’t yet been able to “read”, but that determines what the measurement must be when we measure either of them. So I thought entanglement broke at least one of locality (as I’ve just defined it and which seems now to be completely wrong) and no hidden variables -- one or the other must be untrue for entanglement to work.
Now that I realise you weren’t talking about entanglement, I’m trying to make sense of your comment 69. I read this as you saying that hidden variables would be required to achieve locality in quantum mechanics (and I caught your point that this would be an extension to quantum mechanics because bare quantum mechanics doesn’t have hidden variables) because in quantum mechanics the position of a particle is part of a probabilistic distribution that isn’t resolved into exactness until it’s measured, which in turn makes some other part than location inexact (pardon my vagueness here). But that doesn’t gel with what you said in comment #66, where you said you can have locality or hidden variables, but not both.
So I just don’t understand. Feel free to throw me a link though, with “left as an exercise for the reader”, and I’ll try to edumacate myself.
file thirteen @76: Entanglement, locality and hidden variables are all involved in this discussion.
#69 wasn’t about locality; it was just clarifying what is meant by ‘realism’. #66 said we can’t have locality and hidden variables. That is a result of Bell’s analysis of an entangled pair of spin-1/2 particles. When he assumed locality and a hidden variable for the spin, he found a contradiction.
What he meant by locality was simply this; the way in which you measure the spin at one location does not affect the outcome of the measurement at another distant location.
OK, I think I see the problem. In #69, I said that if you claim that a particle has a definite location, its position is a hidden variable. That use of ‘location’ has nothing to do with the principle of locality. I should have said “if you claim that a particle always has a definite value of property Q (where Q could be position or spin), that property is associated with a hidden variable”.
@Rob:
Thanks for clarifying Rob, both #66 and #69 make sense to me now. 🙂
But then doesn’t entanglement break locality by definition? If the possibility of hidden variables to store “real” spin and “real” position leads to a contradiction, is there any other possibility that preserves locality in each particle of the entangled pair?
Entanglement does imply a non-local effect in most interpretations. So, if the two experimenters measure spin along the same axis, and one of them gets +1, the other one must get −1. It’s as though one measurement instantly “informs” the other one.
The only interpretation in which entanglement is consistent with this notion of locality (unlike the one discussed earlier) is Many Worlds. A bit of math (excluding some details, which I can fill in if you like):
Suppose the axes for spin measurement for experimenters A and B differ by angle θ. (A+) means experimenter A measured the spin as positive along their axis. Then it follows that the probabilities for the various outcomes are:
(A+)(B+): P = (1/2)sin²(θ/2)
(A+)(B−): P = (1/2)cos²(θ/2)
(A−)(B+): P = (1/2)cos²(θ/2)
(A−)(B−): P = (1/2)sin²(θ/2)
Now, in Many Worlds, all of these outcomes are realized, so neither measurement has to “know” what the other one was. Note that, as θ goes to zero, the probabilities for the two measurements being the same also goes to zero.
I should have specified that the results are for spin-1/2 particles in an entangled state of spin zero.
“The only interpretation in which entanglement is consistent with this notion of locality (unlike the one discussed earlier) is Many Worlds”
That’s badly worded. Replace with
“The only interpretation for which this non-local effect is not exhibited is Many Worlds”
Thanks again Rob, that’s brilliant. One more question if I may. Are you able to explain in layman’s terms, only if it’s not too much effort, what the contradiction is that Bell found (mentioned in #77)?
Rob @75
My point was drawing parallels between the three options given for free will in the OP, and the observed uncertainty of quantum mechanics.
Uncertainty seems to allow for determinate and indeterminate both being valid conclusions, without having to calculate or consider stochastic variables.
I meant it as it’s defined in the wiki on Heisenbergs uncertainty principal.
The universe itself would seem to be a wave-like system, as would a solar system, or even a cell?
As long as particles and hidden forces are propagating\in motion (?), matter is in its indeterminate state. They will eventually become determinate, but stochastic effects would be a separate variable in the equation.
I don’t know if magnetic poles are a good analogy for determinate or indeterminate in philosophy, but it helps me to understand how a bit of matter or whole system can contain opposing forces simultaneously without contradiction.
file thirteen @84: I’ll take a crack at that tomorrow.
Tethys @85: I don’t see any parallels, or links, between free will and quantum uncertainty.
I rejected free will as a religious concept, but maintain that living things do have agency which isn’t constrained by reducing everything to physics, quantum particles, and spins.
Living things grow and change. Particles do not. Any complete explanation of agency, determinism, indeterminism, and stochastic effects of living organisms has to accord with quantum mechanics, and we can’t even calculate the variables in wave systems. Thus we set a value for the uncertainty with a standard deviation, but we can’t detail the uncertainty.
@Tethys #88:
Quantum uncertainty only applies at the quantum scale. At macroscopic scales quantum indeterminancy has dwindled away to insignificance. We live in a deterministic world, where the solid walls don’t randomly disolve around us. That’s why it can be said that each of us is deterministic, and has no “free will”. We do what do in the environment we’re in because of what we are.
Thanks file thirteen, but I understand that determinacy is standard at the scale of physical matter and classical physics. Quantum mechanics describes much smaller scale processes, but living organisms do have quantum mechanics happening at the molecular level. Both systems of measurement are needed to describe the physical world, and we haven’t unified them, so it’s a huge leap from wave particle theories to human behaviors.
Photosynthesis, ion gating, and quantum tunneling are all discussed in the Wiki on Quantum Biology. It’s not a simple concept, even at a Wiki level of general information.
.
Since quantum entanglement and complementarity are involved in the basic processes of cell metabolism, I think it’s likely that they are operational at other levels of organization within living organisms.
https://en.m.wikipedia.org/wiki/Quantum_biology
@Tethys #90:
Natural Selection leads to the selections of the most efficient mechanisms that parts of organisms might develop, and efficiency is tied to reliability, which in turn leads to determinism. I think it’s a stretch to say that because cell processes might rely on eg. quantum tunneling, that that makes the cell essentially subject to quantum fluctuations, indeterminancy, and unpredictability as a result. For every physical process that cells use, it speaks more to the efficiency and reliability of that process than of the unpredictability of the cell. IMO.
file thirteen:
No. Good enough is good enough.
(Or, if you prefer, the culling of the insufficiently efficient)
Wrong again John. It’s mathematically simple. The limit as time approaches infinity leads to the most efficient mechanisms. Oh, you thought I was talking about existing organisms, and not the process of natural selection? You never stop to think statements through fully, you pounce on the slightest possible perceived inaccuracy, even though nine times out of ten it’s only an inaccuracy in your head. But do go ahead and write a stupid reply that tries to spin your comment in your favour and misinterpret mine, and don’t forget to end with “Heh”.
Nope.
The irony is palpable.
Yep.
The irony is palpable.
Imitation is the sincerest form of flattery. Ta.
Flattery, mm-hmm. Not drawing attention to the vaccuous nature of your comments, oh no.
file thirteen, either my comments are vacuous or they’re wrong.
Can’t be both.
File thirteen
That’s true, but if it leads to determinism it necessarily implies that indeterminacy is involved in the process before it becomes determined. They are opposite pairs.
Our cells break the laws of classical physics, which is why we now have quantum physics to explain the observations.
They are both measuring aspects of the same thing, and any math system is going to have inherent incompleteness(Gödel) and uncertainty (Heisenberg). But it’s also just our best approximation built entirely of probabilities and averages. It cannot predict or account for stochastic effects, and statistical outliers, which are obviously real.
Rob mentioned magnetohydrodynamics above, and since everything that’s alive has its own self powered electric field it seems logical to assume that any behaviors that emerge from a living collection of particles can be categorized as magnetohydrodynamic processes. Plasma is a very weird state of matter.
https://xkcd.com/1851/
file thirteen @84: Regarding the contradiction Bell found: The set-up:
The experimenter at location A has one of the entangled spin-1/2 particles, the one at B has the other.
The one at A will measure the spin along unit (magnitude 1) 3-vector a, while the one at B uses unit 3-vector b. As usual in QM, each experimenter will either measure spin in the positive direction of their orientation vector (+1), or in the negative direction (−1).
Both experimenters do their measurement, and the product of the measurements is recorded (the product will always be either +1 or −1). With quantum mechanics, we can calculate the average of this product over a large number of entangled pairs of particles. It turns out to be −a·b, where the dot indicates scalar product.
Note that if the vectors are the same (i.e. same alignment and orientation), the product for every pair, and thus the average, is −1, consistent with the above result for unaligned vectors.
That’s the ho-hum QM part. What Bell did was to come up with an expression which should give the same answer as above, based on the two assumptions;
(1) The orientation of a cannot affect the measurement at B, and vice versa. That’s what Bell calls the locality requirement.
(2) The particles have a definite spin even before measurement, which requires some ‘hidden’ parameter, or set of parameters, λ.
So the spin measurement at A is given by some function of a (but not b, from (1)) and λ, and the measurement at B is given by the same function, but with b instead of a.
If the expression built from these assumptions differs from the QM prediction (−a·b), then we have a contradiction, and at least one of the assumptions must be wrong. That is indeed what Bell found.
@Rob #101:
Thanks, that is an excellent description of the issue. Amazingly, I understand. I can’t think of any way around the conclusion.
Correction in #101: should be
“So the spin measurement at A is given by some function of a (but not b, from (1)) and λ, and the measurement at B is given by the negative of the same function, but with b instead of a.”
That’s because, if b = a, the spin measured at B must be the negative of that measured at A.
This got me wondering what exactly religions do in fact say about the concept. Here’s the Catholic Encyclopedia on Free Will, for example -- not the whole thing, but some of the paragraphs covering what the main doctrines of Western Christianity have produced on the topic:
I suspect that some Lutherans and Calvinists might well disagree with some or all of how their doctrines are portrayed.
The Catholic Encyclopedia article on Free Will referenced above begins with an overview:
I note that that last sentence references “control”, which I think is significant.
The Stanford Encyclopedia of Philosophy on Free Will begins with the concept of control:
I think that deterministic vs. nondeterministic and the quantum nature of the universe are red herrings: regardless of how the underlying physical substrate of the universe works, we do not have full control over all of our feelings, thoughts, memories, perceptions, and/or desires. If such full control is necessary for there to be free will, then we obviously do not have free will. I supposed that the compatibilist position is that we have some control (we can learn new behaviors, which can include self-control based on what we’ve learned), and some control is “good enough”, and thus calling the amount of self-control that we do have “free will” is reasonable.
Or something like that. The articles on the topic are long and complex.