Padre Valentim Carvalho wrote: "After he had learned the language, he had access to Ieyasu and entered the palace at any time"; he also described him as "a great engineer and mathematician".
Valentim Carvalho atya így írt róla: „Miután megtanulta a nyelvet, bejárása lett Iejaszuhoz, és bármikor beléphetett a palotába”, valamint „kiváló mérnök és matematikus”.