Hi Derek,

DC> Does anyone have any insight as to why the Satipa.t.thaana Sutta (MN
DC> 10, or DN 22 for the Mahaa- version) uses the expression "atthi
DC> kaayo"?

I pondered this and preceding sentences revealed one more aspect:

"... Or he remains focused on the phenomenon of origination with
regard to the body, on the phenomenon of passing away with regard to
the body, or on the phenomenon of origination & passing away with
regard to the body. Or his mindfulness that 'There is a body' is
maintained to the extent of knowledge & remembrance."

samudayadhammaanupassii vaa kaayasmi.m viharati, vayadhammaanupassii
vaa kaayasmi.m viharati, samudaya vayadhammaanupassii vaa kaayasmi.m
viharati. ‘Atthi kaayo’ti vaa panassa sati paccupa.t.thita hoti.

The triple focus - on origination, on passing away, and on existence -
is often mentioned in many suttas.

Aniccasa~n~na sutta
Samyutta Nikaya 22.102 (III.155)

"Katha.m bhaavitaa ca, bhikkhave, aniccasaññaa katha.m bahuliikataa
sabba.m kaamaraaga.m pariyaadiyati, sabba.m ruuparaaga.m
pariyaadiyati, sabba.m bhavaraaga.m pariyaadiyati, sabba.m avijja.m
pariyaadiyati, sabba.m asmimaana.m samuuhanati?

‘Iti ruupa.m, iti ruupassa samudayo, iti ruupassa attha"ngamo; iti
vedanaa … iti saññaa … iti sa"nkhaaraa … iti viññaa.na.m, iti
viññaa.nassa samudayo, iti viññaa.nassa attha"ngamo’ti ..."

"And in what way developed, monks, in what way practised, the perception
of impermanence exhausts all sensual lust, exhausts all lust for
form, all lust for rebirth, all ignorance, removes all conceit 'I am'?

'Such is form; such is the arising of form; such is the ceasing of
form. Such is feeling, ... perception, ... fabrications, ... such is
consciousness; such is the arising of consciousness; such is the
ceasing of consciousness ..."


There is also an allusion to Bahiya sutta (Udana 1.10)
http://www.accesstoinsight.org/canon/khuddaka/udana/ud1-10.html

"Then, Bahiya, you should train yourself thus: In reference to the
seen, there will be only the seen. In reference to the heard, only the
heard. In reference to the sensed, only the sensed. In reference to
the cognized, only the cognized."

Which may be continued:

In reference to the body, only the body. In reference to the feelings,
only the feelings. In reference to the mind, only the mind. In
reference to the mental qualities, only the mental qualities.

in case of Satipatthana sutta
http://www.accesstoinsight.org/canon/majjhima/mn10.html

Metta,
Dimitry