The Daily Nexus is not known for publishing cutting-edge research in analytical philosophy, but on the 2nd of this month Mr. Jeffrey Robin authored a startling piece in which he advanced a very novel claim of just this sort. Here is the claim in context; just prior to the paragraph I quote below, Mr. Robin suggests that it is no use pondering whether the homosexual poses an existential threat to the marriage institution, given that marriage has been irredeemably fucked for some time.

The shift in attitude and treatment of marriage has come both from society and governmental action. For too much of our history, we have been concerned about where and when people are allowed to sit at the lunch counter or on a bus. This, in turn, has lead to an attitude that everyone has a right to sit anywhere they please. Indeed, if nothing is true than everything must necessarily be permitted.

I do not wish to downplay the importance of what Mr. Robin has to say in the first three sentences of this passage—I entirely share his belief that allowing the Negro to sit anywhere he likes was one of the great stumbles in our nation’s history—but I am here concerned with the last sentence. More precisely I am concerned with the following conditional: “if nothing is true than everything must necessarily be permitted.”

How remarkable! If nothing is true than everything must necessarily be permitted. The profundity of this statement cannot be overstated. In order that we may attempt to grasp it, a formalization is in order:

$¬\exists xTx\to ▫\forall y\left(Ay\to \mathbf{\text{PE}}y\right)$

Here Tx means x is true, Ay means y is an action and PE is the permissibility operator.

Something of a conundrum confronts us if we attempt to move from left to right along this conditional. The antecedent is only satisfied if nothing (presumably no proposition) is true, but if the very conditional proposition if nothing is true than everything must necessarily be permitted is true, then the antecedent is not satisfied.

Can we learn anything by moving right-to-left? It seems plausible (even for a Communist such as myself!) that there are some things which are not permissible: perhaps obstructing the overthrow of the bourgeoisie, or being openly racist in a college newspaper in 2013. In any case, Mr. Robin certainly seems to believe that there are some things that are impermissible: his invocation of this very conditional is part of an attempt to discredit his political opponents by painting them as moral relativists or, worse, as nihilists. So if it’s not true that everything is permissible, then by modus tollens it is not true that nothing is true.

Mr. Robin has established that at least something is true. But unfortunately for him, the undeniable truth that he has established in his article seems to be this one: that Mr. Jeffrey Robin is an imbecile.