english: The nepohualtzintzin mathematical system came out of the necessity that our forefathers had for survival; to till the land they had to count the days, natural phenomena and their cycles, and watch, for instance, that the sun appears every day in the east, goes across the sky and then sets in the west.
non_english: Sistem matematika nepohualtzintzin diciptakan demi memenuhi kebutuhan para leluhur kita untuk bertahan hidup; saat hendak menggarap lahan mereka harus mengamati dan menghitung hari, fenomena alam beserta peredarannya, misalnya, matahari yang setiap harinya terbit dari timur, melintasi langit dan pada akhirnya tenggelam di barat.