 In the Middle Ages the label ‘grammatical sophismata’ was used for the sophismata that dealt with grammatical well-formedness (congruitas) and grammatico-semantic completeness. Sophismata such as ‘Love is a verb’, ‘O Master’, ‘It rueth me’, and ‘I run’ gave rise to very pointed discussions concerning grammatical categories and theories. For example, does a change in word order change the meaning of a proposition? Can a participle be a subject? How should we interpret interjections? Can ‘est’ (‘is’) be used impersonally? 