you don't know anybody's motives, you know only what you are told the motives are (which might not be true), or you see their actions (and you interpret it they way you want to interpret it)
I think he meant that not knowing the leaker's identity meant one can't construct/examine what someone's motives might be. He didn't say anything about (believing) a leaker's claims.
a) A known person who has stated what he believes in and why he does things
b) An organization of unknown individuals, who has stated what it believes, acting on behalf of another unknown individual(s)
You're saying we're in the same epistemological black hole when it comes to evaluating the intentions and consequences-suffered by a) and b)? If so, then OK, that's a philosophical debate that would be really fascinating to discuss on some other day, but pretty much underscores why we won't agree on much in this thread.
you don't know anybody's motives, you know only what you are told the motives are (which might not be true), or you see their actions (and you interpret it they way you want to interpret it)