This paper tries to describe the nature of the subject-area known as philosophy of nursing. It is suggested that attempts to offer such a description are beset with difficulties surrounding both nurses' and philosophers' conception of philosophy. Nonetheless, this paper does seek to offer a description of what philosophy amounts to. Schrock's suggestion that philosophy can be characterised partly by its methods and the distinctive nature of its questions is tentatively endorsed. Her proposal is buttressed with an account of Carnap's distinction between internal and external questions. It is shown that this distinction helps to identify philosophical questions. Further, an attempt is made to show the importance of the distinction between a philosophy of nursing and philosophy of nursing. It is concluded that philosophy involves conceptual analysis and assessment of argument, concern with highly general metaphysical and epistemological questions, and that such questions can be regarded as 'external' questions. It is then shown how these three elements of philosophy also characterise philosophy of nursing.