The so-called "interaction problem" of spiritual/physical

I was explicitly answering Gorgias’s post:

“Note that “apparition detectable by humans” doesn’t necessarily mean that it’s able to be empirically measured. The apparition might not be physical, right?”

Maybe I will go back to the OP, but not at this moment.

Ever hear of a mirage? It exists in the senses although not physically.

When Aquinas talks about “Eucharistic miracles” as such, he talks about the possibilities therein (ST III.76.8 co):


  • in the perception of the beholders, although not physically
  • in the perception of some beholder(s), although not to all
  • in the perception for a period, although not permanently

(We could add, of course, “both in perception and in physical form”.)

And @o_mlly was answering you: it could be a non-physical cause which gives rise to a physical effect (such as when a thought gives rise to physical tears). Similarly, an apparition might be a perception for one, many, or all, without having a physical cause, per se.

OK, let’s start here. The claim is NOT that there are no spiritual beings, rather that there is no reason to assume that they exist.

Let’s correct that assertion: “rather, there is no empirically-verifiable reason to assume that they exist.”

I think we both can live with that, no?

The senses transmit the correct physical information, however, the receiver may incorrectly interpret the physical signals. This does not mean that there are no physical signals.

The neural signals, which rise to the mental state we call “sadness” are also physical. And, of course the mental state is comprised of electro-chemical signals in the brain.

What other kind of verification exists? Remember, the only “window” to the external reality are the signals transmitted through our senses.

Not quite. You have to identify a physical cause that fires those neural signals. A mother who, with no physical sensations, begins to cry demonstrates the existence of a spiritual (immaterial) cause, i.e., thought. Do you agree?

Not if they don’t disturb the reality to the extend which is invisible to our apparatuses. They are very soft.

Ahh, but the physical signals would say “no mirage”. So, if an apparition occurs in the interpretation rather than in the signal itself, it is still an apparition.

Yep. Predictable.

I would argue that mental states are represented physically, and not purely comprised physically. Can you refute that assertion?

Only if you stack the deck by defining “external reality” as something which is exclusively physical. So… how’s that deck stacking working out for ya? :wink:

But aren’t these your parameters? The op is asking about the problem of how we determine the interaction between the spiritual and the physical. If it’s akin to a mirage then, just like a mirage, it doesn’t exist. Our senses have fooled us. And in the case of Zeitoun, a bright light on a roof has fooled people into thinking they saw the Virgin Mary.

And the Vatican obviously doesn’t think it’s genuine. If it were actually the very mother of Jesus Christ appearing to millions then it would be the biggest event in human history. I think they may have said something. But they have taken a sensible stance and gone with the obvious answer as just noted: It was a bright light that some people interpreted as being a figure. A mirage if you like. Not real.

Apparition of Our Lady of Zeitoun

You have been invited many times to give evidence for the non-physical external reality. Each and every time you tried to evade the question, by asking that I should help you and solve the problem for you. It will not work.

Can you provide evidence for the non-physical, or is your view wholly based on blind faith?

I don’t think so. You’re asking a particular question – how do we determine whether this apparition has physical effects that are measurable? – but I was trying to ask a general question about the “interface”, which would speak to any action by spiritual forces in the world.

So… let’s look at your case in particular, without derailing the general question:

In the case of a mirage, what’s happening is that our senses are working just fine – it’s that our brain is misinterpreting what inputs our senses are providing.

The example I gave, with respect to apparitions, is that it’s akin to a mirage (it’s not exactly the same): the assertion is that a spiritual being (God, as it were) is changing not the physical world, but our senses or our interpretation of them. It really is happening, from our perspective, even if there is no physical change that is measurable. And, of course, I’m not asserting that this is the only way an apparition can appear.

Perhaps it has, and perhaps it hasn’t. :man_shrugging:

It’s happened before – this isn’t a singleton event. Lourdes, Fatima, Mexico City – many times.

Are we even talking about the same event? Everything you assert here, I see contradicted in the reports I’m reading. For example, see this article, which makes very different claims about why there’s no official Vatican response, and very different reactions from Church sources…

Oh, I know it won’t work – because you know that what you’re asking for is unreasonable. So, every time I respond to an unreasonable request, asking for clarity, you obfuscate. “Evasion!”, you claim. “Do your own homework!”, you bluster.

I’m doing neither: you’ve made an unreasonable request, and I’ve asked for you to clarify how it might be made more reasonable. When you do not respond to those requests… who’s the one who’s evading? :thinking:

Physical, empirical evidence? C’mon, @Abrosz… you’ve gotta know by now that your game is up. We can see right through your bad faith requests: just admit it, so we can move on.

There is nothing unreasonable to ask for evidence. It is not my job to help you out. You claim (not I) that there is a “spiritual” realm. All I ask is: “present your evidence, any evidence”. And then you asked back:

Maybe you have some very serious comprehension problem. Which part of the “no restriction” don’t you understand? Because I explicitly said that you are free to use ANY method you desire.

I see two possible answer from you. One is to enumerate: “this is my evidence”, which I could evaluate myself, and come to a conclusion. The other one would be admitting that there is no evidence, it is all based on faith.

Now faith based argument can be two kind as well. Either there is SOME non-faith-based evidence, and then it could be evaluated. Or there is none, and then you have a “blind-faith-based” assertion.

That is the situation. Let me repeat: “Which part of no restriction can’t you understand?”.
Read again: “Which part of no restriction can’t you understand?
And a few more times, until you start to understand???

If the evidence is impossible to gather, as such, and you know that this is the case, then yeah… it is unreasonable.

Perfect! Thank you!

OK, the response is exactly what we started this thread off with: unless you can demonstrate a method guaranteed to predict when and how the interactions will take place, then it’s impossible to prepare for and conduct an “empirical evidence gathering” campaign. Glad I could help ya out with that! :wink:

See? No evasion. Just a refutation of the reasonableness of your request!

Then you have answered your own question. There is no ‘interaction problem’.

Which is why I originally brought up Zeitoun. It was a regular event. Lasting for up to an hour each time. Over a period of many weeks. But when we have an example of something you could practically guarantee will occur and that you could most definitely investigate, you say it’s not actually ‘real’. It’s not really there. It’s just God changing our perception of the world.

And to confirm:

Seems like that will cover all ‘interaction problems’ with the physical. You say there isn’t one. You could have said that at the outset to save us all a lot of time.

Ah, so you say that the evidence is impossible to gather… which makes your belief in the “spiritual” unfounded… or based upon blind faith. Glad to see that finally you understand the problem.

That is not my job, it is yours. It is YOU who asserts that “miracles” (or interactions) occur, mine is that they do not. In other words, you BET on the existence of miracles (or interactions), and I BET against them. Are you ready to put your money where your mouth is? I could use some extra cash. :slight_smile:

To clarify: I am willing to entertain YOUR hypothesis, that there is some spiritual realm, and that there is some interaction between it and physical realm. Repeating: “This is YOUR hypothesis, not mine.” Therefore you have two options. One is to admit that your hypothesis is unfounded and based upon some blind faith. The other is that you can demonstrate the interaction. As such it is your task to set up the experiment. Not mine.

I hope you finally understand your conundrum.

Two thoughts:

  • So then, where were the agnostic / atheist skeptics, engaging in the effort to gather data to prove or disprove the apparition? Believers being cool not taking empirical measurements makes sense… but, if it happened over a three year period, where were the so-called lovers of reason and logic, taking measurements to bolster their claims?
  • Even if it were along the lines of an ‘interior’ rather than ‘external’ event, it would still qualify as an ‘apparition’… right?

It really doesn’t. It only covers the question of “apparitions”. Materialists will often pooh-pooh the notion of God’s “sustaining” of the universe, and demand physical evidence of that action.

Neither, thank you very much.

“Unfounded”? Nope – just not verifiable by your personally-beloved methods.

“Based on blind faith”? Again… nope. I use reason and the illative sense to reach a conclusion on the accounts of eyewitnesses. You do the same, but reach a different conclusion. Neither of us is “blind.”

Oh, I’ve understood it since you arrived at the forum. The ‘problem’ is that you think you know better than us, and wish to heckle at every turn. The ‘problem’ is that you’re less rational and open-minded than you’d like to think that you are. The ‘problem’ is that you think you’re smarter than believers.

All of those ‘problems’ are yours, and not ours. I wish you success in working through your problems.

It really isn’t. If you wish to prove that we’re mistaken… then prove it!

We’re not betting ‘cash’, but something far more valuable: eternal salvation. It’s sad to see that you’re betting on the wrong horse.

I do: you’re here to heckle, not discuss. Good luck with that. I’ll continue to defend my position, and refute yours.

There is no evidence of the universe sustaining itself either. Dark matter and dark energy are theoretical artificial constructs to try to explain why the universe has not collapsed following standard astrophysics.

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