# The nature of natural law

Split of from here].

@ Pec of Uliar, While I agree with most of what you said, I do question your proposition that "laws of nature" are descriptive only instead of prescriptive. E =Mc^2 is our description of a function, but the function itself is prescriptive, regardless of description.
No. E=mc² just describes that the total amount of something stays the same, just as the number of H2O molecules does not change when you freeze water to ice. That are just facts about nature. Of course, if you have such true descriptions, then you can use these facts what must happen in other processes. That sounds prescriptive, but it isn't. And that is simple to see: if it turns out that you are wrong, then you must adapt the descriptions. That is daily practice in science.
@ Pec of Uliar, While I agree with most of what you said, I do question your proposition that "laws of nature" are descriptive only instead of prescriptive. E =Mc^2 is our description of a function, but the function itself is prescriptive, regardless of description.
I think we need to be careful here, a description of a function is not necessarily a Law of nature, in this case I would say that the description of the function is a result of the laws of nature, but not the law itself, and while the description might be prescriptive, the laws that produce it may not be. Hmmm. I think I know what you mean, but is this difference not a bit artificial? Say, we have a whole set of laws, differential equations that describe how, dependent on a state at one time, states afterwards develop. Now it turns out that based on these differential equations a quantity of some calculated value (e.g. Sum(E,mc²) before and after the process) is the same. Wouldn't you not call this a law of nature then?

I’m fascinated by this subject.
I don’t accept natural laws are descriptive because I think it only makes sense to use them to work out what would happen if… and to make predictions based on them if the universe is somehow restricted.
Take the collapse of the world trade centre. Some are convinced it didn’t happen as we suppose because that would be physically impossible according to rules we think the universe follows.
But without any restriction, that just produces a shrug of the shoulders, it seems to me.

I'm fascinated by this subject. I don't accept natural laws are descriptive because I think it only makes sense to use them to work out what would happen if.. and to make predictions based on them if the universe is somehow restricted. Take the collapse of the world trade centre. Some are convinced it didn't happen as we suppose because that would be physically impossible according to rules we think the universe follows. But without any restriction, that just produces a shrug of the shoulders, it seems to me.
I don't see the problem. If we see that objects of certain kinds behave at certain ways, and we see they behave like that again and again, why should I suppose that the regularities are prescriptive? Seeing them as prescriptive is in my eyes a category error: one applies the idea of causality on the laws of nature themselves. One thinks that e.g. the law of gravity causes the stone to fall. But that is simply not true. It is the earth that causes the stone to fall down. How the earth causes it is described by the law of gravity. Laws of nature are not things or events that cause other things or events to happen. They describe the regularities we see in how events cause other events.
I'm fascinated by this subject. I don't accept natural laws are descriptive because I think it only makes sense to use them to work out what would happen if.. and to make predictions based on them if the universe is somehow restricted. Take the collapse of the world trade centre. Some are convinced it didn't happen as we suppose because that would be physically impossible according to rules we think the universe follows. But without any restriction, that just produces a shrug of the shoulders, it seems to me.
I don't see the problem. If we see that objects of certain kinds behave at certain ways, and we see they behave like that again and again, why should I suppose that the regularities are prescriptive? Seeing them as prescriptive is in my eyes a category error: one applies the idea of causality on the laws of nature themselves. One thinks that e.g. the law of gravity causes the stone to fall. But that is simply not true. It is the earth that causes the stone to fall down. How the earth causes it is described by the law of gravity. Laws of nature are not things or events that cause other things or events to happen. They describe the regularities we see in how events cause other events. I think merely seeing the laws as descriptive leaves something out. I'm not saying we have to see the as prescriptive exactly. But I do think we need to say nature is restricted somehow so it behaves as we expect. Otherwise it just wouldn't do it.
But I do think we need to say nature is restricted somehow so it behaves as we expect. Otherwise it just wouldn't do it.
Don't you see that there is quite a anthropomorphism in this? Nature is a wild animal that would do all kind of unexpected things, were there not, luckily enough, the laws of nature. I said it already several times, but I'll say it again: there is no reason to say that gravity forces the stone to fall down; with the same right I can say that the stone wants to fall down. Both descriptions are anthropomorphic, and therefore meaningless. I can give you an example: in classical physics there are several mathematical methods to calculate how a particle moves in a gravitational field. Newton's F=ma and F=GMm/r² is not always the easiest one, and depending on the knowledge you have there are different methods: a. Use simple Newton: calculate for a very small time interval what the gravitation does and how the particle moves, to what point, calculate the force there, then take again a very small time interval, do the calculation again, etc. In easy situations, it is even possible to calculate a function for how the particle moves. b. You know the beginning point where the particle is, and you know the endpoint: the question is what trajectory the particle took. There is then a mathematical method where you calculate a certain quantity for every possible path, and then the correct path is the path where this quantity is the smallest of all those paths. (See Lagrangian] for this method) Now does method b. means that the particle does all this calculations and chooses its best path? Of course not! In the same way we must refrain from the idea that the particle is forced in a trajectory, or that it wants to follow a certain trajectory.
But I do think we need to say nature is restricted somehow so it behaves as we expect. Otherwise it just wouldn't do it.
Don't you see that there is quite a anthropomorphism in this? Nature is a wild animal that would do all kind of unexpected things, were there not, luckily enough, the laws of nature. No and here is why. I believe I know you will receive this message. This depends on where we set the bar for knowledge but as long as we set it low enough, you get what I mean. So I'm working with the ordinary definition of knowledge, Justified true belief. The justification is the sticking point. To be justified in my belief I need to be justified in expecting rules that have held so far to continue to hold, so that it's most likely you will receive the message. Well if nature isn't restricted somehow to keep following those rules, it's way more likely that it won't than that it will. The probability of you receiving this message is infinitesimally small considering all the other logical possibilities. It's a miracle that it's followed the rules up to now which is the anthropomorphism bit, but it would be an even greater miracle for it to continue considering the infinite number of other possibilities.
Well if nature isn't restricted somehow to keep following those rules, it's way more likely that it won't than that it will. The probability of you receiving this message is infinitesimally small considering all the other logical possibilities. It's a miracle that it's followed the rules up to now which is the anthropomorphism bit, but it would be an even greater miracle for it to continue considering the infinite number of other possibilities.
You suppose that laws of nature are causes in themselves: rules force electrons to behave as electrons are supposed to do. But if an electron behaves differently, say it is 207 times as heavy as an electron, then we say it is not an electron, but a muon. In science we split up nature according to the regularities we recognise. If some supposed regularity does not hold, then we look for a reason or cause why the regularity does not hold. This scientific program turns out to work. But there is no reason to suppose that the laws of nature are forced upon objects. You may call it a miracle that we can find regularities in nature. But I think it is a simple argumentation from the anthropic principle that such regularities exist: otherwise we wouldn't be here.
@ Pec of Uliar, While I agree with most of what you said, I do question your proposition that "laws of nature" are descriptive only instead of prescriptive. E =Mc^2 is our description of a function, but the function itself is prescriptive, regardless of description.
I think we need to be careful here, a description of a function is not necessarily a Law of nature, in this case I would say that the description of the function is a result of the laws of nature, but not the law itself, and while the description might be prescriptive, the laws that produce it may not be. Hmmm. I think I know what you mean, but is this difference not a bit artificial? Say, we have a whole set of laws, differential equations that describe how, dependent on a state at one time, states afterwards develop. Now it turns out that based on these differential equations a quantity of some calculated value (e.g. Sum(E,mc²) before and after the process) is the same. Wouldn't you not call this a law of nature then? I believe I need to amend myself here. My response was on a different thread under different circumstances, so I think a bit of clarification might help. The term prescriptive was used there in the sense of the laws directing the outcome and I believe that in this sense the idea is correct, the laws do not direct in the sense that outcomes could be different at the whim of some capricious law of nature, but only describe and prescribe what will happen according to fixed laws. However the Natural laws can be prescriptive or predictive in the sense that knowing what the natural laws are in each situation will allow the observer to more accurately predict the outcome. Knowing the laws of nature will lead to knowledge of how objects and creatures might act in different situations, and in this way the natural laws are predictive. Back to the differentiation between a law of nature and the description of the events that are dictated by the laws of nature, the observer needs to be careful to know which one the observer is referring to.
You suppose that laws of nature are causes in themselves: rules force electrons to behave as electrons are supposed to do. But if an electron behaves differently, say it is 207 times as heavy as an electron, then we say it is not an electron, but a muon. In science we split up nature according to the regularities we recognise. If some supposed regularity does not hold, then we look for a reason or cause why the regularity does not hold. This scientific program turns out to work. But there is no reason to suppose that the laws of nature are forced upon objects. You may call it a miracle that we can find regularities in nature. But I think it is a simple argumentation from the anthropic principle that such regularities exist: otherwise we wouldn't be here.
Well unusually for you, you didn't follow my argument at all and are just not addressing what I think or said. Have another look if you want to.
You may call it a miracle that we can find regularities in nature. But I think it is a simple argumentation from the anthropic principle that such regularities exist: otherwise we wouldn't be here.
Well unusually for you, you didn't follow my argument at all and are just not addressing what I think or said. I think I did. So explain in other words what you mean.

GdB
My point was I think we could agree that I knew you were going to receive that message.
But if we take the view of the laws of nature that you are we are forced to conclude I didn’t know.
So we have a contradiction.
That’s why I find it fascinating, how do we overcome the contradiction?

Back to the differentiation between a law of nature and the description of the events that are dictated by the laws of nature, the observer needs to be careful to know which one the observer is referring to.
I don't think I get your point. There is of course a difference in description of events, and a description of the regularities in these events (e.g. compared with other events), but I do not get what you want to say or argue for.
Back to the differentiation between a law of nature and the description of the events that are dictated by the laws of nature, the observer needs to be careful to know which one the observer is referring to.
I don't think I get your point. There is of course a difference in description of events, and a description of the regularities in these events (e.g. compared with other events), but I do not get what you want to say or argue for. I'm responding to the post that the laws of nature are descriptive and not prescriptive. This is something that I hadn't thought much about before and I'm still trying to sort out the details myself. Please disagree, correct and point out my errors and I'll try to get it written more clearly. I think that my point is that the laws of nature are unchanging, it's mans description of these laws that is constantly being corrected and changed as man understands the laws better.
I think that my point is that the laws of nature are unchanging, it's mans description of these laws that is constantly being corrected and changed as man understands the laws better.
I agree with that. Methodologically we cannot really know that, but the successes of at least the hard sciences show that it works that way.

GdB,
Let’s try this. Past regularities either will continue into the future or they will not.
Now if I don’t think nature is restricted some how my conclusion rightly is they will not, since there are so many other possibilities it’s almost certain the actual future will be one of those other possibilities.

GdB, Let's try this. Past regularities either will continue into the future or they will not. Now if I don't think nature is restricted some how my conclusion rightly is they will not, since there are so many other possibilities it's almost certain the actual future will be one of those other possibilities.
Sorry Stephen, it just doesn't work. What you are saying is that laws of nature are causally effective. That is just nonsense. Real laws, in our society, are causally effective. If a rule is made, e.g. that all cars must always have their headlights on during the day, then this (ideally) happens. There is an explanation for how this works, via fines, car drivers being conscious of this rule, etc etc. But in the case of laws of nature there is no such explanation, simply because there is no mechanism that causes events to happen because of the validity of those laws of nature.
GdB, Let's try this. Past regularities either will continue into the future or they will not. Now if I don't think nature is restricted some how my conclusion rightly is they will not, since there are so many other possibilities it's almost certain the actual future will be one of those other possibilities.
Sorry Stephen, it just doesn't work. What you are saying is that laws of nature are causally effective. That is just nonsense. I'm not saying the laws of nature are causally effective. And I think my argument is a good one which is why you are not tackling it head on. I have the option of assuming A) past regularities are laws of nature. Or assuming they are B) just past regularities. If you set things up so I'm right to assume B) you set up a paradox. I say you don't want to look at this. I think it's good to. We might have to say we just can't solve it. But better to say there is an unsolved puzzle than deny it's existence.
I'm not saying the laws of nature are causally effective. And I think my argument is a good one which is why you are not tackling it head on. I have the option of assuming A) past regularities are laws of nature. Or assuming they are B) just past regularities.
But that is the good old induction problem. We have no logically compulsory ground to believe that these regularities will continue. Of course the opposite is also true: we have no logically compulsory ground to believe that these regularities will not continue. But we have the experience that the regularities continue. Obviously, nature is that way. And as said, the anthropic principle shows that it cannot be otherwise: in a nature in which these regularities do not hold, an evolutionary algorithm would not work, so we could never have come into existence. So given this fact, there is no reason to believe that these regularities would not hold. Another reason to believe the regularities hold is the success of science and technology. So in the end, I think it is pretty useless to bring in some methodological argument, that you in your daily life also do not believe in.
Back to the differentiation between a law of nature and the description of the events that are dictated by the laws of nature, the observer needs to be careful to know which one the observer is referring to.
I don't think I get your point. There is of course a difference in description of events, and a description of the regularities in these events (e.g. compared with other events), but I do not get what you want to say or argue for. The laws don't change, only our despriptions do. I agree, it depends which state has Priority, the observer or the observed natural constants.