Gutbone

Since Stephen Colbert is the heart and soul of truthiness, it is generally accepted that the gutbone is both the liver and gall bladder.

Real Americans use their gutbone for thinking. People who use their headbones, Baby Jesus forbid, are Freedom Haters. Truthiness cannot survive in the headbone. Instead, it flourishes in the gutbone. Truthiness also has a secondary habitat in the penis, also something only possessed by Real Americans.