If me turning on the light is a necessary condition for the light being on, then it implies that if I did not turn on the light the light is off. There is no speculation. This is also what distinguishes this one "counterfactual" from all the others.

The article seems to completely ignore that we can readily argue about negative statements. I highly doubt that airplane crash investigators would avoid counterfactuals.

By arguing there are no necessary conditions you are essentially saying we can't use mathematics to describe nature and there are no laws of physics.

For it to fall from the tree? Well, that's a linguistic trick; for it to fall from the tree it must have been hanging on the tree, so that necessary condition is actually a tautology.

Physics describes a world with statistical regularities, not absolute laws. Even a clockwork Newtonian universe is not time-reversible; it has multiple pasts that can lead to the observed present.

Something to be a necessary condition has nothing to do with time-reversibility, it simply states a logical relationship

Let me give you another example: To accelerate a body with mass m it is necessary to exert a force onto it. All mathematical descriptions In fact equivalency, requires conditions to be necessary and sufficient.

Your argument that physics describes a world with statistical regularities is a maybe a nice philosophy, however most physicists (and regular people) do not believe we live in a simulation, but physical laws describe the real world.

E. g. "The apple hit Newton on the head" could be explained by:

1. The apple was hanging on the tree at `t - 1` and the wind shook it loose.

2. The apple was flying through the air because his mother threw it and it collided with his head

3. The apple spontaneously generated due to as-yet-not-understood quantum fluctuations 3 meters above his head.

What they say is that counterfactuals stop the search for the root cause. Not monitoring disk space isn't a root cause of the filled disk. The root cause might be "application has suddenly written too many logs". This gives another set of counterfactuals, like "if your application was configured properly, it would write less logs". But it also gives an option of continuing the search for the root cause, which might be, for example, "there is a bug in the application which triggered the log writes".

I think the point of methods like 5 whys is not to stop at the first set of counterfactuals and deepen the search.

Had the landing gear been retracted in your hypothetical world, then it would be a counterfactual, but it probably wouldn't arise because it's not something out of ordinary - the landing gear retracting is a usual procedure. I think humans are more prone to make the mistake that is described in the article (stopping to search for the root cause) when they see a counterfactual conditional which premise is, in the factual, a procedural error (for example, "operator failed to monitor the disk space"). We see an error and mistake it for the root cause.

To be pedantic, it’s not quite that either. The logic theorem states if A => B then !B => !A. The => means that A is sufficient for B, because “false => true” evaluates to “true” but “true => false” evaluates to “false”. If it were “necessary”, those statements would evaluate the opposite way.

This means that if me turning on the lights is sufficient for the light being on, then the light being off is sufficient to deduce that I did not turn it on.

You are simply stating that me turning on the light is not a necessary condition, but a sufficient condition (which is a reasonable argument).

My argument was that if the statement "if the light is on it was turned on by me" is true (i.e. the me turning on is a necessary condition), then if I did not turn on the light the light is off [edited after mistyping before].

I think this works better with other examples, because as you state, we typically think more of the turning on as a sufficient condition.

Yes, it wasn’t my intent to contradict your overall point, just to correct your logic.

My argument was that if the statement "if the light is on it was turned on by me" is true (i.e. the me turning on is a necessary condition) then it follows that if the light is off, I have not turned it on.

I disagree with you here. The counterfactual, or at least the logic theorem, for the statement [light is on] => [I turned the light on] (me turning it on is necessary for it to be on) is [I did not turn the light on] => [the light is not on]

That’s sound, though it’s not a particularly insightful leap of logic.

If you translate this to the author’s point, they’re basically saying that !A => !B doesn’t tell you that A => B. And that’s correct as far as Boolean logic goes. I am unclear on whether we disagree on that point.

>I disagree with you here. The counterfactual, or at least the logic theorem, for the statement [light is on] => [I turned the light on] (me turning it on is necessary for it to be on) is [I did not turn the light on] => [the light is not on]

Yes you're correct and that's what I corrected my statement to where you managed your reply in between.

However my original statement was:

>If me turning on the light is a necessary condition for the light being on, then it implies that if I did not turn on the light the light is off.

so A=>B therefore !B=>!A. Where A == "light is on", and B == "me turning light on". I agree that it's not particularly insightful.

My point was regarding the statement "The whole point of the article is that you can't get causality from things that didn't happen" from the OP I replied to. That's just not true, we can make statements about causality for things that didn't happen, because we can deduce them from logical conditions.

>If you translate this to the author’s point, they’re basically saying that !A => !B doesn’t tell you that A => B. And that’s correct as far as Boolean logic goes. I am unclear on whether we disagree on that point.

Although we agree in principle I disagree what you say is the authors point.

From the article: >They [counterfactuals] express wishful thinking about an alternate history where the bad event didn’t happen. Because they represent “events that didn’t occur” they cannot have caused anything.

This is a statement I disagree with. To me that sounds that the author essentially says we can not make statements of the type of !A => B (or !B). To me that is wrong and also not a counterfactual. Counterfactuals, are statements about a hypothetical event, i.e. "If I had not turned the light on it would be off now". To me though the author seems to extend the definition of counterfactuals to mean "events that did not happen", maybe he means the correct thing, but both his words and examples do not reflect the correct meaning IMO

It seems like it would be strange to reject as an answer to "why do blind people tend spend less on lighting?" with "Because they don't tend to use the lighting, because the lighting isn't useful to them, so they don't turn the lights on as much (unless someone else who isn't blind is there).".

How else would you answer that question? (modulo little wording changes and such)

But no, in a meaningful sense it's not a true statement about the world. It's a good guess, and for a statement that simple, there might be no need to go further. For a statement about why a volume is full with too many files, the point is that a nice-sounding "if only" isn't something you can test or be certain of.

Your answer about blind people is a very good guess as well, and the same one I would make, but it's not data.

A counterfactual requires posing a situation with changed facts. I stand by my statement, saying "X because not Y" is not a counterfactual on its own. "not Y" is still a (potentially) factual statement. And guesses still aren't counterfactuals. "Maybe the lights aren't on because we didn't flip the switch?" That's a hypothesis, and a testable one. Still not a counterfactual. If we know the flip hasn't been switched, then it's just a fact even if the statement is in the form of not X.

Now consider the opposite. The lights are off because the bulb burnt out. That's a lot less ambiguous. If you want to doubt the causality you've got to get all mystical.