Bishop Berkeley was an 18th cen. Idealist philosopher; Shankara lived (probably) in the 9th century AD and is one of the central figures of Hindu nondualist (Advaita Vedanta) thought. Since I am a freewheeling amateur philosopher instead of an academic, I get to say that these guys, separated by vast gulfs of time and culture, had awfully similar metaphysics.
The central notion here is, in Advaita Vedanta's admirably economic phrasings, "there are not two things" and "thou art that". The idea of individual entities is a provisional illusion caused by the scale at which we observe life; more accurately seen, there is only one thing: Mind.
The Red King is from Through the Looking Glass, where he is asleep, dreaming all of us, and if he wakes up, poof! There we go.
My zeppelin story is an attempt to describe an advanced technological world with empirical sciences and popular literatures based on the nondualistic premise, rather than, as in our world's dominant culture, sciences and literatures based on methodologically reductionist materialism.
See also Wikipedia's discussion of monism.
This stance has always appealed to me greatly, as fulfilling Occam's Razor to precisely the same degree that reductionist empiricism does, in a wholly incompatible manner. It seems to me -- on an emotional level -- that it is most elegant to either disregard qualia, as David Moles says he does, or to disregard everything but qualia.
If we do the former, there is no need to introduce such entities as minds, souls, or divinities; we can simply regard the world as a number of more or less observable particles and forces, distinct from one another each as simple as we can get it; trust only those things we can all verify and agree on together; and regard with suspicion all our thoughts, feelings, attitudes, and experiences, as provisional and misled, proceeding from ultimately inaccurate and erroneous observations of what really is -- the stuff out there.
If we do the latter, there is no need to introduce such entities as forces, particles, matter, or natural laws; we can simply regard the world as the flow of experience, the dream of the dreamer, and read it as such. In this case there is no need to assume that we each have individual consciousnesses or souls, either (as in, say, Samkhya, or C.S. Lewis's Christianity); one soul, perhaps dreaming various dreams, suffices.
The most intellectually, aesthetically, and emotionally satisfying position for me -- in what I consider essentially a nonrational, or prerational matter not amenable to empirical resolution -- is to hold these two positions simultaneously as my guess about the true nature of things, one in each hand, as it were.
(These two worldviews are kind of the inside-out of each other; I think one can be converted to the other by (metaphorically) a kind of reversible transformation that preserves most symmetries).
But maybe there's a third hand, becuase I do have an affection for the traditional monotheistic notion of a sovereign, separate creator God, and that's probably whom I'm most likely to talk to when I talk to the Divine; even if, when I'm thinking philosophically I tend to assume that (as in Hinduism) God, or Goddess, ultimately resolves into one or the other of the above worldviews.
And when David Moles asked me to revise the ending of "Biographical Notes", to come up with some resolution that would go beyond simply "here's their worldview, here's ours, and now I'm stuck hanging from an unpiloted air-boat", that's what I went to, and I think the story is much truer for it. Ultimately, whatever the philosophers say, maybe it's the heart of the devotional mystic -- the Lover of the Unseen Friend (I'm reading Attar at the moment) -- that is the most honest; when we turn from the task of speaking about the world, to the task of speaking to it.
What I tend to be somewhat politically allergic to, though not necessarily utterly disregarding of, is the idea of an interventionist historical God who goes about punishing and rewarding humanity or its subcomponents in brute physical events.
Or maybe not so much the idea of such a God, as the idea of mixing that kind of story with our modern understanding of the world. The Biblical story of Exodus and Numbers, terrible as it is, has an enormous artistic and moral truth and vision seen through the filter of the culture and time from which it comes; it's the attempt to port it with naive literalism to our modern world, and interpret AIDS or tsunamis naively with the same tools, that often seems so frightening, toxic, perverse and immoral.