While conceiving the ill-fated ADORATION OF THE MAGI, Leonardo, who always played out myriad variations on an idea or theme, also created numerous, vibrant drawings for an Adoration of the Shepherds, Nativity, and Virgin of Humility (a northern European convention in which Mary and the Infant Christ are shown seated on the ground) – that is, the whole range of traditional, artistic subjects that dealt with the first days after the Incarnation (fig. 64). The fluidity of his mind was such that the subjects probably evolved with the movement of his pen. This free flow of thought extended as well to the disposition of Saint Joseph, who in some studies has lost the sweet-natured puzzlement one usually sees in Renaissance portrayals, appearing, instead, severe and admonitory. In contrast, on other sheets, Leonardo joyfully imagined the attendant angels as the most nimble and daring of aerial acts and the Christ Child and Saint John as almost acrobatically inclined.