The dream of every teacher is to develop their professional practice with joy and, at the same time, to make their students enjoy learning. The first step is to understand the nature of playfulness, a superior property of human activity. And for this, nothing better than the study of its phylogeny (how playfulness evolved in the human species) and its ontogeny (its development in a particular human being). Therein lie the keys to derive pedagogical actions and didactic strategies in any field of teaching performance.