This paper examines sections of Wittgenstein's "Philosophical Investigations" with a view to exposing trail-effects of psychology in educational and social practice today. These are seen in understandings of the relations between mind and body, and language and thought, and their influence is identified in such contemporary preoccupations as accounting transparency and the new science of happiness. A Wittgensteinian critique is offered, with attention paid to the idea that "nothing is hidden". Finally a question is raised as to how far it is the imperviousness of these practices to criticism that is the key to understanding them.