Again, however, the attractive principle faces a murky reality.

ECONOMIST: Slimming the Bretton Woods duo

The DanKam, an augmented-reality app for iPhone and Android, works on the same principle.

WSJ: New Outlook for Colorblindness

Proponents of this holographic principle believe that all of the complexities of reality contain far less information than common sense would suggest.

FORBES: Flatland?

Yet principle and past suggest that at some point when the gap between actual reality and the vision through the rose-coloured spectacles becomes very large, then the lenses splinter.

FORBES: Despair and Hope Beyond Chairman Bernanke's Monetary Cliff

One hard reality is the emergence of transcontinental alliances of liberals and conservatives, undermining the ancient Christian principle that in each geographical area only one bishop should have authority.

ECONOMIST: When you're a church, breaking up is hard to do