The paradigm of Hindemith's mould of musical thinking was to be the 'Ludus tonalis', a modern-day equivalent of the 'Kunstbuch' although it would go beyond the scope of superficial craftsmanship and constitute an engrossing, concentrated, highly expressive work of musical art.
'I thought I would call the whole thing 'Ludus tonalis' on account of the somewhat didactic (not to say sophisticated) impression that evokes. Our Latin specialists thoroughly approve of the title. I can think of nothing better in English or in German which conveys so unequivocally (and yet so equivocally) what it is and at the same time suggests it belongs to the category (by genus only, not in terms of quality!) as the Well-Tempered Clavier and the Art of Fugue.' Paul Hindemith