Which is true?
-  A limit that one must exceed to reach trueness
-  A game that cannot be won, that one cannot break even with, or that cannot even be exited from (thanks, Asimov!)
-  A measure of a system's gravity (as opposed to levity)
-  Something that System does not have
-  Something like mint tapioca
-  An essential component of Complexity?, as defined by [Information Theory]?
-  Your friend and mine (see Twin)
-  Ataxia, in some way, in either of her forms
-  An obsolete, or at least antique, concept within Puzzleboxian reality
-  Something that can be manipulated
-  The ultimate ineluctability that sentience cannot bear to accept
-  A generic expletive in use by some Top-based factions.
Commentary
The most probable suit distribution in bridge hands is 4-4-3-2, as compared to 4-3-3-3, which is the most evenly distributed. This is because the world likes to have unequal numbers: a thermodynamic effect saying things will not be in the state of lowest energy, but in the state of lowest disordered energy.  
-- R. Schroeppel, [HAKMEM]
More information
[Wikipedia entry]