The perceived problem of the theory-practice gap is built upon the assumption that theory can and must be directly applied to nursing practice, otherwise it is irrelevant. Whilst the spirit in which this claim is made is healthy, the assumption is false. An examination of the Greek origins of theory and practice show that the ancient Greeks had different terms for the different types of knowledge contained within theory and within practice. The type of knowledge associated with practice could not be taught through theory, nor well represented in theoretical terms. The knowledge of the bicycle rider and the piano player illustrate this well. If this is correct then simplistic notions of 'applied theory' are nonsensical. The knowledge of the practitioner is not theory, but something else. However, there is a proper relationship between theory and practice, and there are clear examples of this in the way science informs nursing practice. The problem is that much of this is obscured by the false claim of theorists that nursing theory (such as normative models) is also science. In fact, what it represents is inadequate attempts by theory to represent knowledge which cannot be represented in that form. Nursing is practice, not theory. If so, then the term 'nursing theory' seems to be oxymoronic.