The complexity of inflectional systems

We regard the complexity of any inflection-class system as the extent to which the similarities among its inflection classes tend to inhibit motivated inferences about the word forms realizing a paradigm's cells. We propose ten objective measures of this sort of complexity. We apply these measures in comparing the declensional systems of Latin and Sanskrit, which we represent in a standard format that we call a "plat"; we execute these measurements with an online tool that is freely available for readers to use. We show that the ten measures are not equivalent; together, they show that the declensional systems of Latin and Sanskrit are roughly comparable in complexity. We discuss a number of methodological issues raised by this new approach to typological comparison.