Proof Mind is Fundamental and Matter Doesn't Exist

[Angrboda]

It doesn't follow that because the existence of a solipsistic world can't be proven false that it is therefore possible.  There can be reasons why it can't be proven false in spite of it actually being a false proposition.  Just as in math, that there are propositions which can't be proven to be true doesn't imply that they are false.  Inability to disprove solipsism doesn't imply that it is possible.  The two properties, provability and possibility, are not directly related.  Just as material mind must be directly evidenced, so solipsism requires direct argument for its possibility.

Moreover, you're assuming that a full explanation of mind won't show how matter is essential to mind.  That's an argument from ignorance.

that's why premise 2 states it's unreasonable to presume it's impossible therefore it must be reasonably granted possible. it's saying it's unreasonable to believe what is impossible to prove. would you disagree?

Premises 1 and 2 are a classic argument from ignorance, and hence the conclusion that solipsism is possible doesn't follow.

Argument from ignorance (Latin: argumentum ad ignorantiam), also known as appeal to ignorance (in which ignorance stands for "lack of evidence to the contrary"), is a fallacy in informal logic. It asserts that a proposition is true because it has not yet been proven false (or vice versa). This represents a type of false dichotomy in that it excludes a third option, which is that there is insufficient investigation and therefore insufficient information to prove the proposition satisfactorily to be either true or false.