I think consciousness outside a brain is as irrational a belief as sound inside a vacuum.
I think both claims are about equally impossible things. They are contradictory on the surface.
Yes, that is quite sensible, if you are a materialist it follows rationally I guess.
Well, this comes down to how we regard reality. OK, I'll do this quickly, or I will bore everyone to tears as I'm sure many of you, especially Malerin and Athon and Randfan etc can point out all my mistakes!
We all experience what appear to be two types of thing - A) our
consciousness, me, the thing looks out, and ideas in the mind and B)
matter.
Those are the two basic types of "stuff" in the universe. Matter includes particles, waves, the strong and weak nuclear forces, electromagnetism, gravity, you know the whole energy thing. It's all MATTER stuff.
MIND stuff is well what it sounds like - the stuff of consciousness. We can only really know our MINDS exist - as we experience MATTER Through our minds. Hence Descartes famous phrase usually paraphrased "cogito ergo sum" - I think therefore i am. We can know we exist, we can't know the universe does...
So far, so good.
Now we have to look at the relationship between them
If you believe they are separate types of stuff, you are a
DUALIST. The universe is comprised of mind and matter, and the two must interact in some way or removing your brain would not effect your mind! Penrose has been working on a quantum theory of consciousness which is dualist, and many leading parapsychologists are drawn to this idea because it seems to meet the evidence of some parapsychology.
If you believe that Matter & Mind are the same thing, you are probably a
MONIST. We can divide that in to three separate categories
An
IDEALIST believes that the basic reality is mind - the whole universe is comprised of mind-stuff, and "matter" is created by mind. This supermind is usually equated in Christian Theology with God obviously enough, but our own minds can impact reality, and do. Still there is only one kind of stuff, and it is MIND.
A
MATERIALIST believes there is only one kind of stuff, and is matter. Mind is an emergent property of matter - so our consciousness is nothing more than an emergent property of our brains. The universe is made out of particles, waves and energy, and is physical - this is sometimes called physicalism in fact. Strong materialists like Daniel Dennet and Sue Blackmore say we are not really conscious at all - long story - but
EPIPHENOMENALISM is the normal form. This has the advantage that it seems fairly obvious - most people don't think about MIND being a different type of stuff to MATTER, so it is the "common sense" of science - which by no means means all scientists agree on it, or it is scientifically proven. It's just a default working assumption used to speed things up --
http://en.wikipedia.org/wiki/Naturalism_(philosophy)#Methodological_and_Metaphysical_Naturalism
(if you have time interesting enough.)
The third option, favoured by relatively few philosophers (bertrand Russell is the one who springs to mind) is
NEUTRAL MONISM. Basically this is the idea that neither matter or mind is the real stuff of which reality is comprised, there is a third type of reality which underlies both.
OK, let's just do the wiki links here
http://en.wikipedia.org/wiki/Dualism_(philosophy_of_mind)
http://en.wikipedia.org/wiki/Materialism
http://en.wikipedia.org/wiki/Idealism
http://en.wikipedia.org/wiki/Neutral_monism
Now, can MIND effect MATTER? Well even in the materialist paradigm, yes - because our minds do all the time. I will the words to appear on the screen from my mind, my brain converts them to neural impulses which inform my muscles which type and lo! words appear! According to an epiphenomenalist materialist mind is just a product of highly organized brain matter, so MATTER can give rise to MIND. Many theologians have suggested the transfer can be the other way, and there is no theoretical reason for MIND not to give rise to MATTER, but that is a whole different ball game.
Most hypotheses on mind creating Matter work on the area where the usual rules of matter completely break down - so Mind would work by observing the State Vector at Quantum Event levels and hence creating changes in reality. I can have a go at explaining that if you really want, but I'm not particularly convinced.
(the other are where all this gets really interesting is in Cosmology - the big Bang arising from a Quantum Vacuum fluctuation - but more on that another time.)
For a DUALIST the issue is how the interaction between the two states work. We simply don't know, but theoretically MIND not being constrained to brain but just as real can exist independently. Imagine your brain as a MATTER radio receiver - the signal is MIND. If you break the radio, the signal can continue - life after death for example. We know that if you drink a bottle of red wine or two your brain will be effected, and your mind will have trouble interfacing with reality - but that in no way disproves the hypothesis that mind and brain are different - just as if you put a radio in a cellar the reception may well falter.
Now all this has massive implications for psychical research, and indeed science generally. I could cheerfully talk about them,. but I generally assured I am incredibly boring. Sorry if all this is completely old hat to you, but I'm not sure if they teach it in school anymore, at least before A level Religion which I doubt many of you did, especially if you are American.

(A levels are courses taught in British schools age 16-18, when we tend to specialize in on average three subjects, doing an A level in each.)
So again, if we assume the materialist epiphenomenalist theory of mind/brain sure, your assumptions are very reasonable - but we are still a long way off demonstrating it to be true, even if we ever can.
cj x