Medical science, culture, and truth

There is a fairly closed circle between culture, language, meaning, and truth such that the world of a given culture is a world understood in terms of the meanings produced in that culture. Medicine is, in fact, a subculture of a powerful type and has its own language and understanding of the range of illnesses that affect human beings. So how does medicine get at the truth of people and their ills in such a way as to escape its own limited constructions? There is a way out of the closed circle implicit in the idea of a praxis and the engagement with reality that is central to it and the further possibility introduced by Jacques Lacan that signification is never comprehensive in relation to the subject's encounter with the real. I will explore both of these so as to develop a conception of truth that is apt for the knowledge that arises in the clinic.