How can we talk about Truth, without first consulting the lexicographer Colbert?
Truthiness is a term first used in its recent satirical sense by American television comedian Stephen Colbert in 2005, todescribe things that a person claims to know intuitively or "from the gut" without regard to evidence, logic, intellectual examination, or facts. Colbert introduced this definition of the word during the pilot episode of his political satire program The Colbert Report on October 17, 2005, as the subject of a segment called "The Wørd". Truthiness was named Word of the Year for 2005 by the American Dialect Society and for 2006 by Merriam-Webster.
From the horse's mouth...
BTW: truthiness, being generally indifferent to the actual truth or falsehood of its progeny, has much in common with Harry Frankfurt's "bullshit."