Liberation philosophy seeks to contribute to the liberation of the oppressed and to the creation of a more just society. A meliorative philosophy is one that improves human lives. A liberation philosophy can be regarded as meliorative only if it has a compelling theory of change. A theory of change for philosophical interventions should explain how they can contribute to social, political, or economic change. The main components of such a theory are identified and shown to be present in the work of the best liberation philosophers, such Martin Luther King Jr.. A meliorative philosophy improve human lives by, among other things, providing the kind of guidance that leads to better decision-making and improved conduct. Philosophy should conceive of the guidance it offers as co-created and reflect on the conditions for effective co-creation. The distinctive virtues of meliorative philosophy, including liberation philosophy, are personal qualities that enable co-creation. These include humility, practicality, an openness to diverse perspectives, and an instinct for lived complexity. There are philosophical purists who reject the demand that philosophy should answer to practical needs. We should be sceptical about some of the claims made by philosophical purists.