PlanetMath and PlanetPhysics both exist, whereas PlanetComputing, PlanetEconomics, PlanetEngineering, PlanetStatistics?, PlanetLinguistics, PlanetChemistry?, PlanetBiology?, PlanetLiterature?, PlanetLanguage?, PlanetPhilosophy?, PlanetHealth?, PlanetPlanet?, PlanetAstronomy?, PlanetPolitics?, PlanetLaw?, PlanetHistory?, PlanetMyth?, PlanetFaith?, PlanetBusiness?, etc., don't seem to exist yet, as cool, useful, and imperative to future human existence, as they might appear to be.
Of course, some of these fields aren't traditionally regarded as being "technical" in the sense in which TeX support would be an important deciding factor for the creation of a corresponding Planet. But we can offer TeX support if it is desired, and starting with TeX could certainly work. Support for other languages and standards could come later.
Noösphere, after all, means something like the sum content of all knowledge – the whole world of ideas! I think we should make it our long-term goal to actually cover that territory.
What would distinguish Noösphere from projects like Wikipedia?
Our better support for technical content in general (both via TeX and via any future languages or standards that seem helpful) seems to be a key distinguishing point. With certain kinds of technical content, we can make knowledge "actionable" in ways not possible with less sophisticated systems. It is neither technicality nor actionability alone that sets Noosphere apart, but the ability to switch to these levels (which is wholly missing in Wikipedia as it currently exists; and which seems likely to be missing in any meaningful way until Wikipedia begins to support more sophisticated tools and material).
Where should we get started?
Luckily, we are already well started, so this question doesn't exactly apply. Nevertheless, there is a lot to be done, and I would suggest that we focus on developing good communication tools first, together with test applications. Noösphere and Arxana (and the so-called "Nooxana") are examples pointed in this direction. The thought that should jump out here is that these tools can be used for their own future development, which is why I've put PlanetComputing next on the list above. There is an important adjustment to our focus that comes in to play here: using PlanetComputing to develop tools that will be useful to all Planets would involve an R&D effort, and not simply the reproduction of old content in a new place or form. (This is another feature that sets Noösphere apart from Wikipedia; and although Wikimedia has been responsible for a limited R&D effort, we are now talking about a vastly broader effort, no matter which way you choose to slice it.)
What is the role of PlanetMath in all this?
We've already got a lot of good content in PlanetMath, and we expect PM's content to grow significantly. From the point of view of the other Planets, this is good, since frequently (although of course not always) mathematical tools will be needed when doing analysis related to any of the other topics being examined.
--jcorneli Sun Apr 9 2006
Note: There is a theme that should in some sense cut across all of this, and that is the theme of Natural History. To do a proper natural history of some element of our world requires skills and knowledge of all of the sciences.
I'm using the term 'natural history' because I like the anthropocentic and geocentric connotations. It is 'our' knowledge that makes up our picture of some thing in the world, whether that thing is Alpha Centuri or Cannabis Sativa or Don Quixote.
The point is, I would like to see Noosphere evolve into a master dictionary, where you could look up and find the definition of anything.
--jcorneli
See also: On rebranding PM.org