If science cannot tell us whether these these things are material stuff or mental stuff, we can be sure Idealism cannot do so either.
I agree. I'd put it that when we consider the the question of whether the universe is experiential or material, science can't resolve the question.
Science is backed by a wealth of empirical evidence.Same prob isn't it? ''Empirical evidence'' is experiential. It can't tell us whether we are experiening material or mental stuff.
For Idealism there is none.
Again, the experiential ''empirical evidence'' can work the same for both Idealism and Materialism, yes?
Even if we cannot know what things are in themselves (whatever that means) we know that there is real stuff out there that looks to us like apples, brains etc.
Right, Idealism and Materialism generally agree on that.
Moreover, even if Idealism cannot be disproved, we have no to believe the universe is all mindstuff and much evidence suggesting it is not.
What evidence is left? If science and empiricism can't tell us whether we're experiencing material or mental stuff when we look at an apple or brain or atom, what reliable evidence is there?
It is not clear to me what job you want Idealism to do?
I don't expect Idealism to do anything. I'm not arguing about utility, but the philosophical ontological claims.
What do you think it explains? How does it further our understanding of the universe?
Like materialism, Idealism is a possible explanation for the fundamental nature of the universe.
If everything is mind-stuff why does materialist science work?
I'm saying that calling science ''materialist'' is an assumption, one that's easy to slip into because we take materialism for granted all the time in our daily lives, as does science as a practice.
Idealism is a metaphysical challenge, or alternative, to the assumption that science studies material stuff.
My own position is that our experiential/empirical observations which science uses can be explained by both Idealism and Materialism. It's not a basis for deciding which is correct. I think you agreed with the gist of that when you said - ''If science cannot tell us whether these these things are material stuff or mental stuff, we can be sure Idealism cannot do so either''. ?
That's my point, empiricism and science can't exclude either Materialism or Idealism, or give more weight to one or the other.
Which leads leaves us with the question - if experiential/empirical observation (and science which extrapolates from observation) can't answer which theory is correct, how can we know? Or even assign probabilities?
That's the view which I'm defending - we can't know, or even assign probabilities, about whether Idealism or Materialism is correct. I don't see how either empiricism/science, or reason for that matter, can get us there, even a tool like Occam's Razor can cut both ways here.