Do non-verbal number systems shape grammar? Numerical cognition and Number morphology compared

Number morphology (e.g., singular vs. plural) is a part of the grammar that captures numerical information. Some languages have morphological Number values, which express few (paucal), two (dual), three (trial) and sometimes (possibly) four (quadral). Interestingly, the limit of the attested morphological Number values matches the limit of non-verbal numerical cognition. The latter is based on two systems, one estimating approximate numerosities and the other computing exact numerosities up to three or four. We compared the literature on non-verbal number systems with data on Number morphology from 218 languages. Our observations suggest that non-verbal numerical cognition is reflected as a core part of language.