This paper argues that Donald Winnicott can be understood as an organicist psychoanalyst, whose theory of development aligns with the major conceptual shifts that took place in twentieth-century biology. The study outlines how organicism replaced mechanicist and vitalist explanations with frameworks emphasising emergence, form, relational fields, and development over uninterrupted time. Central to this shift was the increasing scientific attention to potentiality, understood as a dispositional property that becomes manifest only under the right conditions. The paper demonstrates that Winnicott’s concepts of the True Self, continuity of being, and inherited potential correspond to this organicist logic. Although Winnicott does not explicitly reference biological organicists, his claim that “there is no such thing as a baby” already implies a field-based model of development. The conclusion highlights that Winnicott’s theory participates in a broader scientific transformation: the recognition that living beings — including human psychological life — must be understood as emergent, relational, and teleologically organized systems rather than mechanical assemblages.