My point is that because all known reasoning takes place in physics, we don’t need to assume that any of the other things we talk about exist in the same way that physics does.
I can’t follow your syntax, but clearly physical brains can think about non physical things.
It’s a mistake because it’s impossible for us to have evidence in favor of its existence, but we do have evidence against it: that evidence is known as Occam’s Razor.
But it’s not conclusive in every case, because the simplest adequate explanation need not be a physical explanation.
clearly physical brains can think about non physical things.
Yes, but this is not evidence for the existence of those things.
But it’s not conclusive in every case, because the simplest adequate explanation need not be a physical explanation.
There is one notion of simplicity where it is conclusive in every case: every explanation has to include physics, and then we can just cut out the extra stuff from the explanation to get one that postulates strictly less things and has equally good predictions.
But you’re right, there are other notions of simple for which this might not hold. For example if we define simple as “shortest description of the world which contains all our observations”. Though I think this definition has its own issues, since it probably depends on the choice of language.
Still, this is the most interesting point that has been brought up so far, thank you.
Edit: I was too quick with this reply and am actually wrong that my notion of simplicity is conclusive in every case. I still think this applies in every case that we know of, however.
Edit 2: I think the only case where it is not conclusive is the case where we have some explanation of the initial conditions of the universe which we find has predictive power but which requires postulating more things.
Yes, but this is not evidence for the existence of those things.
I didn’t say it was.
But it’s not conclusive in every case, because the simplest adequate explanation need not be a physical explanation.
There is one notion of simplicity where it is conclusive in every case: every explanation has to include physics, and then we can just cut out the extra stuff from the explanation to get one that postulates strictly less things and has equally good predictions.
Why posit that an explanation has to include physics even in cases, like this, where it adds nothing? In those cases it’s simpler not to include physics.
I can’t follow your syntax, but clearly physical brains can think about non physical things.
But it’s not conclusive in every case, because the simplest adequate explanation need not be a physical explanation.
Yes, but this is not evidence for the existence of those things.
There is one notion of simplicity where it is conclusive in every case: every explanation has to include physics, and then we can just cut out the extra stuff from the explanation to get one that postulates strictly less things and has equally good predictions.
But you’re right, there are other notions of simple for which this might not hold. For example if we define simple as “shortest description of the world which contains all our observations”. Though I think this definition has its own issues, since it probably depends on the choice of language.
Still, this is the most interesting point that has been brought up so far, thank you.
Edit: I was too quick with this reply and am actually wrong that my notion of simplicity is conclusive in every case. I still think this applies in every case that we know of, however.
Edit 2: I think the only case where it is not conclusive is the case where we have some explanation of the initial conditions of the universe which we find has predictive power but which requires postulating more things.
I didn’t say it was.
Why posit that an explanation has to include physics even in cases, like this, where it adds nothing? In those cases it’s simpler not to include physics.