Ten years ago the Oxford Dictionaries (OD) picked the word “truthiness” as their word of the year to best express evolving political mores – it described the phenomenon of “believing something that feels true, even if it isn’t supported by fact”. This week for 2016 they picked “post-truth”, as in “post-truth politics”, marking the sad downward spiral in public discourse in a decade from a need at least to aspire to truth to its abandonment. “Post-truth”narrowly beat first cousin “alt-right”, the ideological bent of Breitbart News, home of post-truth journalism.
OD define "post-truth" as "relating to or denoting circumstances in which objective facts are less influential in shaping public opinion than appeals to emotion and personal belief". Telegraph sketchwriter Michael Deacon accurately captures its essence as: "Facts are negative. Facts are pessimistic. Facts are unpatriotic." And in a vain attempt to fight back, Glen Kessler of the Washington Post, fact-checker extraordinaire, has created a star rating system, "Pinocchios", to rank offenders. Donald Trump has amassed such a collection of Four-Pinocchio ratings – 59 in all – "that by himself he's earned as many in this campaign as all other Republicans (or Democrats) combined in the past three years".
But the concept is philosophically problematic. Consider the truth of the phrase “we live in a post-truth society”. If true, then it is false. If false, it is a truth. The proposition is a logical paradox akin to Bertrand Russell’s famous “Barber of Seville” who shaves everyone who does not shave himself. Does he then, Russell asks, shave himself? How can he? The challenge, as logicians explain it, involves considering the set of all sets that are not members of themselves. Such a set appears to be a member of itself if and only if it is not a member of itself.
Logical theory resolves the conundrum by suggesting that “sets” and their “members” are like apples and pears and cannot be compared. In this case, although the truth of “we live in a post-truth society” cannot be logically considered, it does, however, have the quality of “truthiness”.