A) Yeah, uh, in Science, when we refer to 'things that exist', we usually mean 'materially' and not 'in fantasy'. So no, that it is an 'idea' does not mean 'it

A) Yeah, uh, in Science, when we refer to 'things that exist', we usually mean 'materially' and not 'in fantasy'. So no, that it is an 'idea' does not mean 'it exists'. B) Prove to me that dark matter exists. Characterize it. You can't. The only thing we know is that our equations for gravity don't work, and it would be 'nice' if there were this thing called 'dark matter' out there because it would fit nicely with what we previously understand. So - there's plenty for me to argue with. C) Dark Matter/Energy theory basically states the Universe is made up of 96% of this interesting material we don't know for sure exists, we have no direct evidence of it, and we really can't characterize it very well. When a principle is '96% wrong' - maybe it would be better to question the very nature of the principle, instead of trying to fit it to observation? It's highly possible that our understanding of gravity is just plain wrong. That we can make some inferences in our locality, but in the grand scheme it just falls apart. Obviously, it is wrong to the tune of 96%. Which is not good. There's going to be a lot to 'argue about' with Dark Matter/Energy for the next couple of generations at least.