After 50 years of research, mathematics education still has learning problems as witnessed by the PISA studies. So, a suspicion arises: Can we be sure that what has been undertaken is mathematics and education and research? We seek an answer in philosophy by listening to Heidegger that, wanting to establish its meaning, finds two forms of Being: that what is, and how it is. In a Heidegger universe, the core ingredients are I and It and They, where I must neglect the gossip from They to establish an authentic relationship to It. Bracketing mathematics’ gossip will allow its root, Many, to open itself and disclose a ‘many-matics’ as a grounded natural science different in many ways from the traditional self-referring set-based mathe-matics. So to improve its educational sentences, mathematics should bring its subjects to the classroom, but leave its gossip outside.