It also addresses the issue of observing "the body in the body" (the locative kaye) as part of the same extended interpretation. Lots of other nice little bits, too.Briefly, the first three satipaṭṭānas correspond to three facets of the self as it is
presumed to exist as a substantial, fixed thing. Each of the exercises within this
scope challenges this presumption by demonstrating that bodily, percipient and
mental evidence for the presumption is lacking, primarily through recognition
the impermanence of the evidence in contrast with the presumption. It is the
distinction between evidence and presumption that gives us the dichotomies
referred to in “internal and external”....
...what we contemplate “internally” is the observable bodily
“evidence,” based on the instructions of the preceding exercise itself. I will call
this contemplation “internal analysis.” What we contemplate “externally” is the
body as a facet of the self, which is a “presumption” of a substantial, fixed
thing. When we contemplate both “internally and externally,” we are asking,
Are these the same? We discover that we cannot reconcile the presumption
with the evidence. I will call these final two contemplations “external
analysis.”
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