There are basic elements (dhatu), when only visible to the ordinary human eye, such as earth & space, the give the impression of being non-composite. For example, a grain of sand on a massive sand dune in the Sahara desert. It may not be obvious how the arising of this grain of sand occurred. This grain of sand may have an impression of permanence. But the grain of sand of obviously a sankhata (conditioned thing). The internet says:
The Sahara Desert formed around 7 million years ago, as a great dust
bowl sitting where the Tethys sea once soaked. This huge body of water
separated the two supercontinents, Laurasia and Gondwana, resulting
from the cleaving of Pangea by tectonic forces.
Similar, the element of space may appear to be a non-composite phenomena. But, in realty, the element of space is conditioned by the absence of the element of form or water in that space. About the element of space, MN 62 says:
And what is the space element? The space element may be interior or
exterior. And what is the interior space element? Anything that’s
space, spacious, and appropriated that’s internal, pertaining to an
individual. This includes: the ear canals, nostrils, and mouth; and
the space for swallowing what is eaten and drunk, the space where it
stays, and the space for excreting it from the nether regions. This is
called the interior space element. The interior space element and the
exterior space element are just the space element. This should be
truly seen with right understanding like this: ‘This is not mine, I am
not this, this is not my self.’ When you truly see with right
understanding, you reject the space element, detaching the mind from
the space element.
MN 62
For example, if the nostrils are blocked with mucus, the element of space reduces or disappears.
As for 'conventions' - like 'a chariot' - they also are characterized by arising, ceasing and enduring because they are thoughts. In SN 22.59, the Buddha says any type of sankhara aggregate is impermanent. MN 148 literally says 'mind-objects' have been discerned to arise & vanish (dhammānaṁ uppādopi vayopi paññāyati).
If we still remain with doubt about this, the convention of 'a being' in SN 5.10 is exactly the same as 'jati' in Dependent Origination. 'Jati' is the coming forth & production of conventions of 'beings within a class of beings'. About 'jati', SN 12.20 & SN 22.81 say:
Birth is impermanent, conditioned (sankhata), dependently arisen, subject to destruction, vanishing, fading away, and cessation.
SN 12.20
Assumes form to be the self. That assumption is a fabrication. Now
what is the cause, what is the origination, what is the birth, what is
the coming-into-existence of that fabrication? To an uninstructed,
run-of-the-mill person, touched by that which is felt born of contact
with ignorance, craving arises. That fabrication is born of that. And
that fabrication is inconstant, fabricated, dependently co-arisen.
That craving... That feeling... That contact... That ignorance is
inconstant, fabricated, dependently co-arisen.
SN 22.81
The idea 'conventions' are not subject to the characteristics of conditioned things appears found in the mass-market commentary Abhidhammattha Sangaha & is wrong.
As Nibbàna is eternal it does not belong to the past, present, or future. It is timeless. So is pannatti, independent of time.
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