Κεφαλισμός

"Aristotle calls 'multiplication-tables' the products of the first numbers up to ten.¹ For through exercise with them, the products of the latter with [sc. numbers] larger but similar to them are explained by analogy: for, from twice two is four, one realizes that twice twenty is forty, and that twenty times twenty is four hundred, and that two hundred times twenty is four thousand, and similarly one after the other."²