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The Three Layer Causal Hierarchy [pdf]

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Re: The Three Layer Causal Hierarchy [pdf]

#11

Post by Retra »

ced wrote: post #6
Retra wrote: post #5

Earlier quoted context omitted.

That's far too little logic to be a counterexample here. Rain correlates with a lot of things. If you were to stop all of those things , you could surely stop the rain as well. For instance, if rain is correlated with clouds, and you get rid of clouds, you'll get rid of rain. The fact is, there does not exist this thing you've called 'rain' that causes people to be wet and does nothing else relevant to your argument.…

What do you mean by structural simplifications?

What I mean is that it is possible that when we speak of causality, we are speaking of a specific subset of correlative structure, and that the features of those correlations that make them causal are matched with far greater significance against our usage of the term 'causal' than the features of correlative relations that do not take part in causal structure.

Like if I say "blue", you can very quickly simplify by assuming I'm talking about the color blue, rather than all the other things in the world that are also called 'blue', even though there's nothing that necessitates this simplification.

Re: The Three Layer Causal Hierarchy [pdf]

#12

Post by mistersheik »

Retra wrote: post #5
ced wrote: post #4

Earlier quoted context omitted.

I'll try... Rain causes people to be wet. This implies that if we were to God-like stop the rain, people wouldn't be wet. But if we were to prevent people from being wet (by buying them an umbrella), that wouldn't stop the rain. This is not something you can infer from correlations alone.

That's far too little logic to be a counterexample here. Rain correlates with a lot of things. If you were to stop all of those things , you could surely stop the rain as well. For instance, if rain is correlated with clouds, and you get rid of clouds, you'll get rid of rain. The fact is, there does not exist this thing you've called 'rain' that causes people to be wet and does nothing else relevant to your argument.…

> If you were to stop all of those things, you could surely stop the rain as well.

By the way, this is not true in general. Suppose B…F are sampled from Boolean variables with bias 0.5. A Boolean circuit like A = (sum(B,C,D,E,F)>3) + (not B and not C and… not F). A is correlated with all of its causes B through F. However, stopping all of its causes, causes A to turn on.

> If you were to stop all of those things, you could surely stop the rain as well.

But, you typically can't intervene everywhere. For example, you may not have any power over the gardener who normally turns the sprinkler on. The point of interventions (like turning a sprinkler on) is that you can reason about what would happen.

Re: The Three Layer Causal Hierarchy [pdf]

#13

Post by Bromskloss »

mistersheik wrote: post #10
Retra wrote: post #5

Earlier quoted context omitted.

That's far too little logic to be a counterexample here. Rain correlates with a lot of things. If you were to stop all of those things , you could surely stop the rain as well. For instance, if rain is correlated with clouds, and you get rid of clouds, you'll get rid of rain. The fact is, there does not exist this thing you've called 'rain' that causes people to be wet and does nothing else relevant to your argument.…

We do have a great formalization of causality, which is Pearl's book.

Doesn't he assume that causal relationships exist, and then show how to make calculations with them?

Re: The Three Layer Causal Hierarchy [pdf]

#14

Post by mistersheik »

Bromskloss wrote: post #13
mistersheik wrote: post #10

Earlier quoted context omitted.

We do have a great formalization of causality, which is Pearl's book.

Doesn't he assume that causal relationships exist, and then show how to make calculations with them?

Yes. Are you arguing that the world does not have causal relationships? Such a world doesn't even make sense to me.

Re: The Three Layer Causal Hierarchy [pdf]

#15

Post by Bromskloss »

mistersheik wrote: post #14
Bromskloss wrote: post #13

Earlier quoted context omitted.

Doesn't he assume that causal relationships exist, and then show how to make calculations with them?

Yes. Are you arguing that the world does not have causal relationships? Such a world doesn't even make sense to me.

I'm not arguing either way. I just don't know how I can decide one way or the other.

Re: The Three Layer Causal Hierarchy [pdf]

#16

Post by ced »

Retra wrote: post #11
ced wrote: post #6

Earlier quoted context omitted.

What do you mean by structural simplifications?

What I mean is that it is possible that when we speak of causality, we are speaking of a specific subset of correlative structure, and that the features of those correlations that make them causal are matched with far greater significance against our usage of the term 'causal' than the features of correlative relations that do not take part in causal structure. Like if I say "blue", you can very quickly simplify by a…

when we speak of causality, we are speaking of a specific subset of correlative structure,

Yes, I agree. Just like linear models are a specific subset of quadratic models.

than the features of correlative relations that do not take part in causal structure.

In my mind, causality is an additional set of modeling assumptions that greatly enhance our ability to do logical and probabilistic inference.

Re: The Three Layer Causal Hierarchy [pdf]

#17

Post by ced »

Bromskloss wrote: post #15
mistersheik wrote: post #14

Earlier quoted context omitted.

Yes. Are you arguing that the world does not have causal relationships? Such a world doesn't even make sense to me.

I'm not arguing either way. I just don't know how I can decide one way or the other.

IIRC Pearl has a chapter on "Where does causality come from?" and "Can there be causality without time?" I don't remember the conclusion unfortunately. IMO causality is a strict consequence of the time-based physics of our universe. The future was caused by the past. Animals evolved from primordial bacteria, not the other way around.

Re: The Three Layer Causal Hierarchy [pdf]

#18

Post by mannykannot »

Retra wrote: post #5
ced wrote: post #4

Earlier quoted context omitted.

I'll try... Rain causes people to be wet. This implies that if we were to God-like stop the rain, people wouldn't be wet. But if we were to prevent people from being wet (by buying them an umbrella), that wouldn't stop the rain. This is not something you can infer from correlations alone.

That's far too little logic to be a counterexample here. Rain correlates with a lot of things. If you were to stop all of those things , you could surely stop the rain as well. For instance, if rain is correlated with clouds, and you get rid of clouds, you'll get rid of rain. The fact is, there does not exist this thing you've called 'rain' that causes people to be wet and does nothing else relevant to your argument.…

If you were to stop all of those things, would that not include stopping the causes of rain, if they exist? (For that matter, is that why you can say 'surely' in that sentence?) If we thought we knew the causes of rain, and happened to be correct (both that there are causes and in what we think they are) then should we not be able to predict what, short of stopping all of those things, would stop the rain, without having observed that happen?

Re: The Three Layer Causal Hierarchy [pdf]

#19

Post by Retra »

mistersheik wrote: post #12
Retra wrote: post #5

Earlier quoted context omitted.

That's far too little logic to be a counterexample here. Rain correlates with a lot of things. If you were to stop all of those things , you could surely stop the rain as well. For instance, if rain is correlated with clouds, and you get rid of clouds, you'll get rid of rain. The fact is, there does not exist this thing you've called 'rain' that causes people to be wet and does nothing else relevant to your argument.…

> If you were to stop all of those things, you could surely stop the rain as well. By the way, this is not true in general. Suppose B…F are sampled from Boolean variables with bias 0.5. A Boolean circuit like A = (sum(B,C,D,E,F)>3) + (not B and not C and… not F). A is correlated with all of its causes B through F. However, stopping all of its causes, causes A to turn on. > If you were to stop all of those things, you…

"B...F" are not all the causes of A. You forgot to include the relation "f(B...F)", whose existence is also strongly correlated with A, as per the entire justification for using that '=' symbol the way you have.
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