When speakers make grammatical errors, linguists typically label them “slips” or “speech errors” and qualify them as episodic phenomena. However, repeated deviations from the linguistic norm, for example the dropping of postpositions, as in “Thanks for having me” instead of “Thanks for having me on”––the near-ubiquitous response of radio call-in guests––or “caving” instead of “caving in” and “bailing” instead of “bailing out” should not so insouciantly be ignored as merely aleatory.

Grammar is not just a set of rules characterizing linguistic behavior. It is the reflection of patterns of thought that have been codified as the received form of expression of grammatical relations. The coherence of these patterns is, naturally, not etched in stone, but innovations in grammar that are patently incoherent––such as the dropping of postpositions, or the mindlessly redundant generation of pleonasms––should be recognized for what they are, namely failures of thought, and rooted out as inimical to one’s mental health, as an instance of linguistic pathology.