This article sets out key contributions to the long-running debate about mental disorder from the ordinary language philosophy of the ‘Oxford School’. The distinction between definition and use of concepts underpinning ordinary language philosophy reframes the debate as a debate not just about mental disorder but about disorder in general, bodily as well as mental. The field work of ordinary language philosophy (focusing on the use of concepts as a guide to their meanings) shows that, attempts at elimination notwithstanding, there (...) is an essential evaluative element in the meaning of disorder, bodily as well as mental. The concept of disorder in the debate thus reframed presents a double challenge for analysis: to explain why disorder has evaluative connotations used of mental conditions but descriptive connotations used of bodily conditions. Philosophical value theory, derived by applying ordinary language philosophy to the language of values, provides a rich resource of ideas for meeting this double challenge. It meets the double challenge at the level of theory by allowing both aspects of the double challenge of disorder to be derived from a logical property that disorder shares with all other value terms. It meets the double challenge at the level of practice by supporting the development of a new approach to working with values alongside evidence in healthcare called values-based practice. Ordinary language philosophy, notwithstanding these several contributions, is no panacea. It helps us to make a start, no more and no less, in understanding mental disorder. (shrink)