Lois Shawver associates Foucault with postmodernism through Lyotard:
Lyotard (1993) defines postmodernism as an incredulity towards metanarratives. A metanarrative is a theory or story that passes itself off as a truth without exception, generalized truths that pretend to be true for all objects in a category, such as all Priests are pure, all people in a certain country think a certain way, or science is the best approach to solving all human problems.
Shawver describes Foucault's view of the doctor's clinical gaze as avoiding "the esotericism of knowledge and the rigidity of social privilege" by being
acquired through his observation of patients. The wisdom was a practical wisdom that was supposedly learned through internships and apprentiseships not by dipping into the texts that told of professional secrets.
This objectivity (detachment) provides the needed isolation from book knowledge and social privilege.
The OP suggests that this clinical gaze is similar to the detachment of Buddhism. There may be similarities, but this gaze is also part of a metanarrative toward which postmodernism wants to take a critical stand. One may have a gaze detached from social privilege without the social acceptance that makes the gaze a metanarrative.
Here are other forms of gazing that would be similar to both the clinical gaze of the doctor at the bedside of a patient or the detached gaze of the Buddhist in meditation.
Consider a priest beloved by his congregation holding up a host during the transubstantiation phase of a Catholic Mass.
A trusted fortune teller gazing (scrying) into a crystal ball or looking at the pattern made by a selection of Tarot cards.
Or, to bring this home, someone thinking about (gazing at) the notion of a "clinical gaze" and writing down those thoughts.
Not all of these are part of modern metanarratives the way Foucault claims the clinical gaze is. What makes the clinical gaze of doctors significant for Foucault is this currently believed metanarrative. If Sawver is correct this is what would make Foucault a postmodernist according to Lyotard's definition.
Shawver, L. Notes on reading the Birth of the Clinic. 16 May 1998.
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