This article clarifies how the freedom of thought as a human right can be understood and promoted as a right of mental health service users, especially people with psychotic disorder, by using Martha Nussbaum’s capabilities approach and Fulford’s and Fulford et al’s values-based practice. According to Nussbaum, freedom of thought seems to primarily protect the capability to think, believe and feel. This capability can be promoted in the context of mental health services by values-based practice. The article points out that both Nussbaum’s approach and values-based practice recognise that people’s values differ. The idea of involving different actors and service users in mental healthcare is also common in both Nussbaum’s approach and values-based practice. However, there are also differences in that values-based practice relies on a ‘good process’ in decision-making, whereas the capabilities approach is oriented towards a ‘right outcome’. However, since process and outcome are linked with each other, these two approaches do not necessarily conflict despite this difference. The article suggests that absolute rights are possible within the two approaches. It also recognises that the capabilities approach, values-based practice and human rights approach lean on liberal values and thus can be combined at least in liberal societies.