In Paul Guyer's Kant, section "A Life in Work", the author claims this:
this argument from synthetic a priori cognition to the subjectivity of what is cognized is independent of the general premise that whatever is characteristic of sensibility is merely a matter of how things appear to us.
"This argument" is presumably this:
we can have synthetic a priori cognition of the structure of space and time only if we have a priori representations of space and time and indeed only if space and time are nothing but those a priori representations, or the a priori forms of all of our sensible representations of particular objects.
I'm barely understanding why "this argument" is true, although I think I get the general idea of it, and I didn't hope to understand it in depth since we are only in an introductory historical section.
However, Guyer makes that note about the independence of the conclusion to the premise, and I'm thinking that if it is here, it must be important, and it must be intelligible with the tools that I have so far.
So, how is this independence important, and true? Should I be worried about not having a clue why that sentence is here?