[colemannugent]

>We actually have no scientific evidence either way.

That's how we know it's nonsense. When there's no evidence for something it doesn't mean that it's 50% Likely to be true.

If I told you there's a dragon in my garage you should immediately think that I'm lying because you've never seen any prior evidence of dragons anywhere.

Mathematically, things with no evidence for their existence don't exist.

[wk_end]

Sagan’s Dragon doesn’t really apply here, though. Because, while we don’t have evidence for something non-physical behind mind, we do have a phenomenon - conscious subjective experience - occurring with no real physical explanation anywhere in sight. Or even conceivable, really. Chalking it up to a specific religious idea of a soul or anything is a bridge too far, of course, as is believing anything one thing with more fervor than just a hunch, but...

Well, the analogy falls apart because whether there’s a dragon in the garage really is something physically verifiable, and it’s hard to know if where the there that’s there comes from is. But it’s a little like if you occasionally heard loud stomping noises or roars coming from your garage, and things in there were turning up with big bites taken out of them or singed with fire. No matter how much you look you can’t find the cause. Is that a dragon? Dragons don’t exist...but who knows?

[joeberon]

Yeah I definitely agree with this. Many people can and do perceive the inexplainable issue directly. I had a discussion about that recently here on HN, about those who can perceive a "hard problem of consciousness" and those who cannot. Basically some people do not perceive any disparity between a totally physical model of the mind and our conscious subjective experience, while I and others personally do. It is a bit tiring to constantly be called delusional because I feel that disparity

[joeberon]

Right but the idea that there are aspects of our minds that don't exist within this physical universe is not outlandish or bizarre, it's a very reasonable and historically defended position.

EDIT: Also not sure what this bizarre statement is:

> Mathematically, things with no evidence for their existence don't exist.

1. How is that related to mathematics? Can you provide a theorem or some definitions here?

2. How is evidence related to mathematics?

3. Why is mathematics relevant when talking about whether or not our mind has non-physical aspects?

[colemannugent]

>...the idea that there are aspects of our minds that don't exist within this physical universe is not outlandish or bizarre...

That's where we disagree. Can you give me an example of anything that doesn't exist within this physical universe? I'm not familiar with the concept of a "thing" that isn't physical.

Sorry about being confusing with the last sentence. I'll try and address your questions:

1. When we talk about the likelihood of something being true we are now discussing probabilities, which have a long and well proven track record of obeying the laws of statistics. Statistics are quite often counter-intuitive and our brains don't think in terms of the math that governs the actual outcomes

A good example is the birthday problem [1]. Imagine we had a room full of people and we wanted to know what the odds are that two of those people in the room had the same birthday. Obviously the more people we have, the more likely we are to have a match, but how many people do you need to get to that point?

It turns out that with just 23 people in the room there's a 50% chance of two people having the same birthday. Most people's intuition leads them to believe that for 50% you'd need 365/2 = 182.5 people, but once there's 70 people in a room, you're almost certain to have a match with a probability of 99.9%. This is a good example of a case where not knowing the math will lead your predictions of the world to be incorrect.

2. When we discuss evidence we are trying to figure out the probability of something, thus the rules of probabilities apply. One of the fundamental theorems of statistics is Bayes' Theorem [2], which at its core tells you how to calculate the probability of an event given another event.

To motivate that, here's a more realistic example: "A patient goes to see a doctor. The doctor performs a test with 99 percent reliability--that is, 99 percent of people who are sick test positive and 99 percent of the healthy people test negative. The doctor knows that only 1 percent of the people in the country are sick. Now the question is: if the patient tests positive, what are the chances the patient is sick?"

If you answered 99% then you'd not only be wrong, but you'd have misdiagnosed your patient. The correct answer here is 50% [3].

3. To bring it all together: to properly know things one must understand the laws of mathematics. This applies not just to problems that obviously involve probabilities, but everything in general.

At it's core, I think our disagreement revolves around this idea of non-physicality and the belief that there are things that aren't governed by mathematics. Everything is physical and obeys the laws of physics which themselves are governed by the laws of mathematics.

[1] https://en.wikipedia.org/wiki/Birthday_problem

[2] https://en.wikipedia.org/wiki/Bayes'_theorem

[3] https://sphweb.bumc.bu.edu/otlt/mph-modules/bs/bs704_probabi...

[joeberon]

Is "mathematics" a thing in our physical universe? Many people argue it's an abstract set of constructions with no physical reality in themselves. Sounds kind of outlandish and bizarre according to your criteria.

> Everything is physical and obeys the laws of physics which themselves are governed by the laws of mathematics.

If you define "physical" to mean "literally everything" then of course having something outside of Physics is logically impossible. That is a different definition to the work "physical" that we are working with in terms of the mind. In that case "physical" doesn't mean "literally everything" but rather more like "those things that correspond to an external, verifiable, objective reality". For you, ideas and concepts would be considered physical, but that is not the case for the definition of "physical" I mentioned, which is far more common in both religion and philosophy.

In this case we would say that ideas and concepts are not physical. So an easy answer to your question "Can you give me an example of anything that doesn't exist within this physical universe? I'm not familiar with the concept of a "thing" that isn't physical." would be literally any concept or idea. However since you have a universalist (and thus totally useless) definition of "physical", of course it is impossible for me to argue that there is anything outside of that.

PS. As a doctor in quantum physics myself, I can tell you that statistics and probability is certainly a way of modelling outcomes, and not in any way considered a fundamental element of reality.

[colemannugent]

I'm afraid I still don't understand. Are you arguing that there is some utility in considering "concepts or ideas" non-physical from an ontological perspective? Because I think we both agree they're solidly physical in the sense that a "thought" can be reduced to chemical signaling.

On the QM side, I'm pretty sure that you're incorrect in your postscript. It was my understanding that certain physical processes can only be understood though probability and that talking in terms of wavefunctions is the most correct way to do that.

[joeberon]

> Because I think we both agree they're solidly physical in the sense that a "thought" can be reduced to chemical signaling.

I don’t agree with that. I think there is an inseparable spiritual element that justifies the subjective experience.

For the QM part, that still does not mean that ontologically the probabilities have a physical reality. Google “interpretations of quantum mechanics”, we have very little idea of what quantum mechanics actually means yet. We can set up the problems and do the maths but no one even knows what exactly it means to do a measurement (again Google “measurement problem”). I am an expert in quantum mechanics (it is my job) so I would be happy to answer questions about it in the morning.