A simple argument against freewill. Miracle?
I'm not a scientist but Newtonian physics applies at the quantum level. If I'm correct that means particles, their position and velocity, are deterministic in behavior.
Knowledge of initial states of particles can be used to predict their properties at some other time in the future.
We're physical, our brains are physical i.e. we're all made up of particles. That implies our brains are deterministic machines if you'll allow me to use that word.
If that's the case then freewill shouldn't exist. It's existence would violate the laws of nature and it would be a true miracle. This can't be.
Your comments...
Knowledge of initial states of particles can be used to predict their properties at some other time in the future.
We're physical, our brains are physical i.e. we're all made up of particles. That implies our brains are deterministic machines if you'll allow me to use that word.
If that's the case then freewill shouldn't exist. It's existence would violate the laws of nature and it would be a true miracle. This can't be.
Your comments...
Comments (65)
[quote=Wikipedia]In quantum mechanics, concepts such as force, momentum, and position are defined by linear operators that operate on the quantum state; at speeds that are much lower than the speed of light, Newton's laws are just as exact for these operators as they are for classical objects. At speeds comparable to the speed of light, the second law holds in the original form F = dp/dt, where F and p are four-vectors.[/quote]
What do you think?
It's still a script :joke:
And that irons out the irony.
You lost me. I've always heard it's random, so I don't know?
:smile:
everything follows
is it free, my will?
an uncaused skill?
laws, break and bend?
look here my friend
even in chaos random
behold! laws therefrom
what free? what will?
peach tree, peaches fill
an exception no?
like in a freakshow?
it could be you know
something against the flow
Good poem!
Who's the scribe of my slab written upon?
I ask myself whether I’m stylus or slate,
Or both the dancer and the danced upon?
Not true. Newtonian physics is strictly deterministic. Quantum mechanics is not.
Quoting Sunnyside
That's true but imprecise. Quantum mechanics is probabilistically deterministic. This means there is not one discrete possible outcome; rather, there is a well-defined probabilistic distribution of possible outcomes.
I'm having some trouble with this, could you explain it to me?
The physical is something that only exists in our heads. How then can we be physical if we contain the physical?
There are things that happen all the time at small scales (with real and obvious effects at large scales) that seem to be truly random. Some interpretations try to restore a deterministic picture, but usually at the cost of some other intuition that we tend to hold, like realism, locality, or counterfactual definiteness.
Even such things as whether a single photon will reflect from or pass through a glass surface appear to involve real randomness.
Not so. It applies at all levels.
A quantum mechanical system evolves over time in strict accordance with a time-dependent Schroedinger equation. This means that at every point in time, the system is in a deterministic quantum state.
A quantum state is a multivalued vector; i.e. it's not a discrete number, but rather a set of numbers - where "number" is referring to something that can be measured. Prior to measurement, all the values exist simultaneously, in what's called a "superposition". When a measurement is made, only one of the values will be measured. Across multiple measurement, the set of measured values will be consistent with a well-defined probability distribution.
Do you agree that a system can be considered deterministic if it evolves over time strictly per an equation over time? That is the case with a quantum system. (I'll defer your question about measurement until you consider this).
So one comment is that "I'm not a scientist" should be emphasized there.
Why are you proposing that quantum mechanics is deterministic, exactly?
That's a good way of putting it, for the probabilities add to 1, this being what is called 'unitary'.
The tricky part is that a measurement does something. What it DOES is subject to interpretation, and there are a variety of interpretations of quantum mechanics. For example, according to the "Copenhagen" interpretation, a measurement causes the wave function to collapse (the Schroedinger equation defines a wave): prior to measurement, all the eigenvalues exist concurrently; after the measurement only one exists: the wave function has collapsed to the single value.
By contrast, in the "many worlds" interpretation, a measurement entails the measurer becomes "entangled" with a single eigenvalue, but the others continue to exist - but not within the world wherein lies the measurer. From the point of view of the measurer, this looks the same as the Copenhagen interpretation.
It is unpredictable which eigenvalue will be collapsed to (Copenhagen) or experienced (Many Worlds), but it is a certainty that it will be one of them, and the probability for each is known. This is not strict determinism, but it is probabilistic determination. This is the term used by physicalist philosopher David Armstrong. The connotation is that these states are still the product of physical laws of nature.
It is a self-evident truth of reason - one you yourself appeal to - that free will is incompatible with our decisions having been antecedently determined.
But it is even more powerfully self-evident that we have free will.
Consider: in the lengthy debate over free will the majority of those who have thought long and hard about the issue still conclude that we do, in fact, have free will. They either conclude that compatibilism is true, or they conclude that incompatbilism is true but that the indeterminism is says is necessary for free will actually obtains (libertarianism). Only a minority (albeit quite a significant minority) conclude that we lack free will. So evidently most of those who think long and hard about this issue recognise that it is powerfully self-evident to reason that we possess free will.
So this premise:
1. We have free will
is exceptionally powerfully supported by our rational intuitions.
Less powerfully supported, by powerfully supported nevertheless, is this premise:
2. Free will is incompatible with everything we do being antecedently determined (that is, if we have free will, then not everything we do is antecedently determined)
The conclusion that follows from these two premises is this:
3. Therefore, not everything we do is antecedently determined.
But as you point out, this premise is also true:
4. If we are physical things, then everything we do is antecedently determined
And what follows from 4 and 5 is this:
5. Therefore we are not physical things.
Shush… they're listening. Too late; here come the white coats; we're all mental!
Hello argument!
Quoting Bartricks
Now, really, who's going to notice a slight tape-like delay to consciousness?
But we can be informed by brain-consciousness correlation experiments and neurology…
So, the speed of light is infinite and any processing time is infinitely fast? OK. Time to go mental.
I, as the conscious thing, am my own cause, or causeless?
Either way, where/when does it get its information?
Apart from you begging the question by stating as a premise the very thing I want to prove/disprove, I find your post very interesting. The problem with the lacunae in our body of knowledge that is evident in discussions on topics like free will is that we tend to speculate. This isn't a bad thing but we tend not to make progress and instead offer each other our own conceptions of the issue. Thanks for your views. There's a lot of work that needs to be done.
:ok:
Yes, I'm not a scientist but the Wikipedia article clearly states that particles follow Newtonian physics. I'll quote wikipedia article on Newton's laws of motion below:
[quote=Wikipedia]In quantum mechanics, concepts such as force, momentum, and position are defined by linear operators that operate on the quantum state; at speeds that are much lower than the speed of light, Newton's laws are just as exact for these operators as they are for classical objects. At speeds comparable to the speed of light, the second law holds in the original form F = dp/dt, where F and p are four-vectors.[/quote]
Quoting petrichor
Can you show me why? Thanks
Yes, consciousness is difficult to explain but within existing knowledge paradigms there is no need to assume anything else.
Sure!
link
link
Classical physics and quantum physics are incompatible descriptions of the world. Though classical physics provides a good approximation in many macroscopic scenarios.
While a quantum state evolves deterministically (as a superposition of states), measurement is non-deterministic (returning a single definite state per the probabilities given by the Born rule). Explaining the latter given the former is known as the measurement problem.
Quoting TheMadFool
I think of it this way. Suppose Alice prefers tea to coffee. If Bob models her preferences accurately, then he will make successful predictions about what she chooses to drink. Yet his model is simply descriptive. The model does not determine what she will drink - Alice does.
Similarly scientists can construct equations that describe the behavior of particles and, in principle, any natural system, including human beings. Yet those equations, even if deterministic, are descriptive not prescriptive.
As long as human choice is considered to operate within the context of natural causality, then there is no miracle or unresolvable conflict. Human beings can make choices based on their preferences AND be described mathematically. If there is a conflict, then it is the math that needs to change to reflect the observed behavior - the math is not prescriptive.
Not quite - whether there are multiple versions and what is considered real is an interpretive issue. What is universally agreed on is more like this:
If you send a photon through a beam splitter, the quantum state evolution (according to the Schrodinger equation) is:
(1) Photon enters beam splitter
(2) Photon transmitted + Photon reflected
That's deterministic, with state (2) represented as a superposition of two simpler states. When the photon is measured at a detector, you observe just one of those simpler states, e.g.,
(3) Photon reflected
The Schrodinger equation doesn't give (3). Instead the Born rule predicts (3) with 50% probability. The measurement problem is concerned with what (2) means and what measurement involves such that (3) is observed.
As for large objects, they mostly effectively behave like classical physics would predict because the De Broglie wavelength is very small, but effectively is important here.
A single subatomic particle has a fair amount of uncertainty associated with its position and momentum. Put it in a box, look to see where it is, and more than likely, it'll still be in the box. But there is still a significant chance you'll find it outside, which is quite counterintuitive. But take a basketball, and matters are different, but not because it is fundamentally different. If you put a basketball in a box, you'll never come back to find it outside. This is not because there is nothing random here, but rather because it is composed of so many particles. To find all of them, at the same time, suddenly one foot to the left would be astronomically unlikely. If you roll one six-sided die there is a 1 in 6 chance you'll roll a 6. But roll a trillion dice. What are the odds you'll roll sixes on all of them at the same time?
But this isn't the end of the story. There are many ways in which the large uncertainties associated with single small particles can be amplified in such a way that they have large effects on macroscopic objects. You could, for example, measure the spin of a particle and use the result to determine the state of a switch on a train track, such that if the particle is spin up, the train goes to Chicago, and if spin down, it goes to New York. This makes a very large event random.
In fact, when we do measurements and make the results visible to ourselves, we are doing just this. We are amplifying quantum effects.
It isn't inconceivable that such amplifications could happen in such things as biological systems. After all, we have signaling mechanisms operating at very small scales, where in some cases, quantum uncertainties could be large enough to have effects on the behavior of the system. Such sufficienty small mechanisms have not yet been shown to be important in large scale brain behavior, but this isn't completely off the table just yet.
All that said, it is hard to see how randomness is compatible with what we think of as free will. If it is random, it isn't willed. If it is determined, it isn't free. Regardless, I think it is premature for us to rule out free will, as consciousness, time, matter, causality, and so on, are still very mysterious, very poorly understood. Personally, my intuition that I act freely and willfully is so strong that I distrust the ways in which these matters have been presented and understood in human history thus far.
1. If everything we do is antecedently causally determined, then we lack free will.
2. If we are physical things then everything we do is antecedently causally determined
3. Therefore, if we are physical things then we lack free will
4. We are physical things
5. Therefore, we lack free will
What I am doing is arguing that the above argument is weaker than this one:
1. If everything we do is antecedently causally determined, then we lack free will
2. If we are physical things, then everything we do is antecedently causally determined
3. Therefore, if we are physical things then we lack free will
4. We have free will.
5. Theefore we are not physical things.
My argument's premises are all well supported by reason and its conclusion contradicts no truth of reason. But your argument has one premise that is no supported by reason - your premise 4 is just an assumption, not a self-evident truth of reason. And your conclusion contradicts self-evident truths of reason.
Speaking of amplification of quantum effects, quantum cosmology is an interesting area to look into!
Sure. You may find this comparison of the various interpretations useful, of which de Broglie-Bohm theory and Many Worlds are the main deterministic interpretations.
Prove it!
https://www.physlink.com/education/askexperts/ae392.cfm <---that's the standard view in physics. That's not to say that it's correct, but it's the conventional view.
The word "particle" is ambiguous. Thanks.
A particle, as a field quantum, is spread out, as kind of a lump.