Teaching has moved gradually from being seen as an art or craft to an evidence-based techno-rational profession. However, within Steiner-Waldorf schools, teachers are largely autonomous and seen, like their pupils, as always "coming into being", through the development of an objective imaginative faculty. This perspective is derived from Steiner's spiritual research and draws on Goethe's scientific method, which is explored here. How this may manifest in practice will be illustrated with some examples from recent data on the early professional development of new teachers. Development of the imaginative faculty, it is argued, is a requirement for becoming an authentic teacher.