I believe it was Clarke that mentioned that Heinlein's political beliefs depended on who he was having sex with that month.

Yeah, he's the hardest to pin down of the 20th century masters of sci fi. LeGuinn wears her heart on her sleeve and while she explores ideas, she has a consistent direction. Herbert demands critical thinking (if the entire book is Paul terrified of the evil of him leading the jihad, what does it mean when he leads the jihad at the end). Asimov is out there exploring ideas, but you can figure him out (it's been a long time since I've read him). And Clarke is pretty consistent in his distrust of those who desire power.