The grammar of numerals is a complicated chapter in Classical Arabic treatises because it lies at the junction of many grammatical rules. In his Kitāb, Sībawayhi (d. 180/796?) analyzes numerals as a category of substantives resembling the adjectives that themselves resemble active participles, aiming at a deep consistency between all grammatical rules. In the Muqtaḍab, al-Mubarrad (d. 285/898) visibly prefers to collect as many peculiar cases as possible where numerals are involved, renouncing consistency at a wider scale. Lastly, in his ʾUṣūl, Ibn al-Sarrāj (d. 316/928) creates a specific grammatical category for numerals, systematizing a trend initiated by al-Mubarrad and initializing a way of analyzing grammar that seems to be predominant until the present day in the grammar of numerals.
What has the grammar of numerals become in later grammarians? Did they refine Ibn al-Sarrāj’s systematic and exhaustive subdivisions? In this paper, I intend to explore Raḍī l-Dīn al-ʾAstarābāḏī’s (d. 688/1289?) grammar of numerals in order to understand how he deals with this complicated chapter of Arabic grammar. Each theory has its blind spots, i.e., assumptions that make vision possible but that are not questioned per se. Can we infer Raḍī l-Dīn al-ʾAstarābāḏī’s blind spots in his grammar of numerals? Could he escape the blind spots of his predecessors?