You see - you can prove it, with one of these. You just need to know the wavelength of the light which will tell you where it is on teh spectrum which will (in most cases) be able to be proved to be a certain colour (except for those "No it's yellow" "no it's not it's orange" conversations.)

[st d] Whether you can prove it or not wasn't the point - it was whether you needed to prove it, or indeed whether you even needed to know a proof was possible.

of course - silly me.

[st d] Well done though.

Wow, this moves fast...
Raak] If by the case of Iraq you mean the resistance against the US/British occupation, then I'd agree that they are morally justified (without necessarily meaning that each and every one of the resitance's actions are morally justified). I suspect that's not what you mean though.
I think the core problem here is where you say "That is the key difference between empirical knowledge and moral knowledge: one is demonstrable and the other is not." If moral knowledge is not demonstrable in some way, then how do we learn it, other than by faith? And given that there are lots of possible belief systems, many of which disagree very strongly with each other, how do we distinguish between right and wrong belief systems?

Darren] I still don't see how you can know whether a proof is possible, without knowing how you are testing it.