user13375: It is generally taught in Mahayana monastic universities that Theravada does not posit the selflessness of phenomena. There it is taught a dichotomy exists between the tenet systems employed by various Buddhist traditions:

The selflessness of persons
The selflessness of phenomena

In Mahayana texts it is often said that the self of persons and the self of phenomena comprise the "two selves" that are refuted. It is said that Theravada only posits and thus refutes the self of persons.
This is a commentary on a textbook used in Buddhist monastic universities in India/Tibet written by a Geshe Lharampa:

For the, "Vaibashika school, there are 3 divisions and 18 subschools,
  one of which is the Theravadan school)"
...
Selflessness of phenomena is not asserted because the Vaibashikas
  assert that an established base is pervaded by self of phenomena i.e.
  even though the V assert selflessness of person, they do not assert
  the selflessness of phenomena.
Within existence, there are two aspects – person and phenomena. When
  one talks about selflessness of person, one is referring to the
  concept of “I”. When one talks about the selflessness of phenomena,
  one is referring to one’s 5 aggregates, all outer objects and
  everything other than concept of “I”. The V school doesn’t assert the
  selflessness of phenomena because they hold the view that phenomena is
  truly existent from its own side.

Emphasis in the original. The point I think is that a dichotomy is made between persons and external objects. The former is said to lack a self, but external objects are considered to be real or truly existent. Some Mahayana tenet systems say the latter also are unreal and not truly existent.
What do self-identified Theravada proponents think of this? Is this how you'd characterize your school or you understanding? Do you identify with the Vaibashika school?

user-1: I decided that I will add my two cents about things existent or truly existent. The problem of misunderstanding is common in Buddhism among nearly all the writers that write about Eastern ideas. Masters, scholars and spiritual leaders are no different. Writers have tendency to often oversimplify complex systems where they should be giving explicit and elaborate descriptions leaving clarity. This leads to confusion as there are phrases rich in many implicit meanings (oversimplifications) that cannot be understood by neither ordinary person, nor even moderate Buddhist practitioner.
As a result, there is finally the prevalent confusion about whether things exist or don’t exist, and whether things are of Selfless nature or not, and what does it really mean. In truth, those are two separate questions to be addressed, regardless of school context.
The first question is easily discarded by Buddha in Kaccayanagotta Sutra:

Everything exists': That is one extreme. 'Everything doesn't exist': That is a second extreme. Avoiding these two extremes, the Tathagata teaches the Dhamma via the middle (...)

Here, we can only say that things are somehow real and existent, and that would be accurate. Claiming that things exist or don’t exist is a Metaphysical fool’s play with no end. Unfortunately, some commentators do engage in such unsolvable disputes. Comparing such attempts would be like comparing these to solving Gordian’s knot riddle, or other unsolvable mysteries of life.
Therefore, Theravada could not have had it any different than Mahayana when it comes to existence or non-existence.
And rather than exploring these extremes in futile attempts we should explore the Middle as it is real to be experienced here and now. And this is the second question, question about Selflessness of phenomena: When things appear to us, how do they appear, what is their true nature?
The answer to this question is not elaborated nor directly tackled by Theravada, so here, it might or might not be different - it is up to scholar’s interpretation.
But when Nagarjuna says “Samsara is Nirvana” it means that two truths - conventional and ultimate, are in fact one; concepts and fantasies arise from the touch with the way reality really is (tathata). There isn’t really much more to it.
It doesn’t take a great meditator and enlightened being to expand understanding and come up with such conclusions as Nagarjuna did, this is something we already know by intuition. Emptiness is natural, whether inner or outer, because phenomena are not how we picture them. Why? Because we see through the lens of Self framework, and this Self context coming from subject observer experience that infests the nature of things, contextually velcroing Self onto anything we experience. And that is because we cannot easily unlearn to think in other way and unlearning this habit requires great deal of insight. If validity of such wrong perception wasn’t the case in the first place, the loud noise at night wouldn’t make person afraid of the possible robbery. Why? Because here, we are afraid of losing Self by clinging to our very life and well-being, hence we distort reality of things by Self-centered “I” reference. It is the same for anything else, for instance, the deluded object of desire; the context here is Selfish, achieving the object for our own pleasure and satisfaction due to grasping. Looking at the flower we might consider it beautiful as it arouses pleasure, which is again, Self grasping by isolating pieces of reality, singling elements out to form a pleasurable fantasy. 
It does not mean that flower has “ego-Self”, but that we see it through our Self scope and this is how it appears to us. In Yogacara it is described in detail as distortion of direct perception of consciousness by interaction with Manas (Self grasping mind faculty). And that’s it. If one is caught up in semantics about “Self” due to objects not capable of having an ego, it is more correct to say that things don’t have “intrinsic essence” rather than to say that they are Selfless. But it is not saying that things “don’t exist” and it is not this sort of debate here, it doesn’t relate to the second question at all.

user471: 
The Vaibashika school doesn’t assert the selflessness of phenomena
  because they hold the view that phenomena is truly existent from its
  own side.

In my opinion, the Theravada view according to the Pali suttas imply that:

The self (of persons) is not truly existent.
Whether non-self phenomena are truly existent from its own side or not, is (probably) not important towards the path to the end of suffering. (See the Parable of the Poisoned Arrow, Parable of the Simsapa Leaves and the Discourse on the Unconjecturables)

Of course, there may be a lot of Theravadins out there who dispute my second statement above, and would assert that all non-self phenomena are truly existent from its own side.
EDIT: Just to make it clearer:
All sankharas (conditioned and/or compounded things) are subject to change, arising and passing. Nibbana is not subject to change, arising and passing. Both sankharas and nibbana are empty of a self. But this does not mean that sankharas and nibbana are not truly existent. The self is definitely an illusion, but the world, transient as it is, may not be an illusion. Whether the world is an illusion or not, is not important to the path to the end of suffering (according to Theravada, in my opinion).

13375: <p>It is generally taught in Mahayana monastic universities that Theravada does not posit the selflessness of phenomena. There it is taught a dichotomy exists between the tenet systems employed by various Buddhist traditions:</p>

<ol>
<li>The selflessness of persons</li>
<li>The selflessness of phenomena</li>
</ol>

<p>In Mahayana texts it is often said that the self of persons and the self of phenomena comprise the "two selves" that are refuted. It is said that Theravada only posits and thus refutes the self of persons.</p>

<p>This is a commentary on a textbook used in Buddhist monastic universities in India/Tibet written by a Geshe Lharampa:</p>

<blockquote>
  <p>For the, "Vaibashika school, there are 3 divisions and 18 subschools,
  one of which is the Theravadan school)"</p>
  
  <p>...</p>
  
  <p><strong>Selflessness of phenomena is not asserted because the Vaibashikas
  assert that an established base is pervaded by self of phenomena</strong> i.e.
  even though the V assert selflessness of person, they do <strong>not</strong> assert
  the selflessness of phenomena.</p>
  
  <p>Within existence, there are two aspects – person and phenomena. When
  one talks about selflessness of person, one is referring to the
  concept of “I”. When one talks about the selflessness of phenomena,
  one is referring to one’s 5 aggregates, all outer objects and
  everything other than concept of “I”. The V school doesn’t assert the
  selflessness of phenomena because they hold the view that phenomena is
  truly existent from its own side.</p>
</blockquote>

<p>Emphasis in the original. The point I think is that a dichotomy is made between persons and external objects. The former is said to lack a self, but external objects are considered to be real or truly existent. Some Mahayana tenet systems say the latter also are unreal and not truly existent.</p>

<p>What do self-identified Theravada proponents think of this? Is this how you'd characterize your school or you understanding? Do you identify with the Vaibashika school?</p>
 -1: <p>I decided that I will add my two cents about things existent or truly existent. The problem of misunderstanding is common in Buddhism among nearly all the writers that write about Eastern ideas. Masters, scholars and spiritual leaders are no different. Writers have tendency to often oversimplify complex systems where they should be giving explicit and elaborate descriptions leaving clarity. This leads to confusion as there are phrases rich in many implicit meanings (oversimplifications) that cannot be understood by neither ordinary person, nor even moderate Buddhist practitioner.</p>

<p>As a result, there is finally the prevalent confusion about whether things exist or don’t exist, and whether things are of Selfless nature or not, and what does it really mean. In truth, those are two separate questions to be addressed, regardless of school context.</p>

<p>The first question is easily discarded by Buddha in Kaccayanagotta Sutra:</p>

<blockquote>
  <p>Everything exists': That is one extreme. 'Everything doesn't exist': That is a second extreme. Avoiding these two extremes, the Tathagata teaches the Dhamma via the middle (...)</p>
</blockquote>

<p>Here, we can only say that things are <em>somehow</em> real and existent, and that would be accurate. Claiming that things exist or don’t exist is a Metaphysical fool’s play with no end. Unfortunately, some commentators do engage in such unsolvable disputes. Comparing such attempts would be like comparing these to solving Gordian’s knot riddle, or other unsolvable mysteries of life.</p>

<p>Therefore, Theravada could not have had it any different than Mahayana when it comes to existence or non-existence.</p>

<p>And rather than exploring these extremes in futile attempts we should explore the Middle as it is real to be experienced here and now. And this is the second question, question about Selflessness of phenomena: <em>When things appear to us, how do they appear, what is their true nature?</em></p>

<p>The answer to this question is not elaborated nor directly tackled by Theravada, so here, it might or might not be different - it is up to scholar’s interpretation.</p>

<p>But when Nagarjuna says “Samsara is Nirvana” it means that two truths - conventional and ultimate, are in fact one; concepts and fantasies arise from the touch with the way reality <em>really is</em> (tathata). There isn’t really much more to it.</p>

<p>It doesn’t take a great meditator and enlightened being to expand understanding and come up with such conclusions as Nagarjuna did, this is something we already know by intuition. Emptiness is natural, whether inner or outer, because phenomena are not how we picture them. Why? Because we see through the lens of Self framework, and this Self context coming from subject observer experience that infests the nature of things, contextually velcroing Self onto anything we experience. And that is because we cannot easily unlearn to think in other way and unlearning this habit requires great deal of insight. If validity of such wrong perception wasn’t the case in the first place, the loud noise at night wouldn’t make person afraid of the possible robbery. Why? Because here, we are afraid of losing Self by clinging to our very life and well-being, hence we distort reality of things by Self-centered “I” reference. It is the same for anything else, for instance, the deluded object of desire; the context here is Selfish, achieving the object for our own pleasure and satisfaction due to grasping. Looking at the flower we might consider it beautiful as it arouses pleasure, which is again, Self grasping by isolating pieces of reality, singling elements out to form a pleasurable fantasy. </p>

<p>It does not mean that flower has “ego-Self”, but that we <em>see it</em> through our Self scope and this is how it appears to us. In Yogacara it is described in detail as distortion of direct perception of consciousness by interaction with Manas (Self grasping mind faculty). And that’s it. If one is caught up in semantics about “Self” due to objects not capable of having an ego, it is more correct to say that things don’t have “intrinsic essence” rather than to say that they are Selfless. But it is not saying that things “don’t exist” and it is not <strong>this sort of debate here</strong>, it doesn’t relate to the second question at all.</p>
 471: <blockquote>
  <p>The Vaibashika school doesn’t assert the selflessness of phenomena
  because they hold the view that phenomena is truly existent from its
  own side.</p>
</blockquote>

<p>In my opinion, the Theravada view according to the Pali suttas imply that:</p>

<ol>
<li><p>The self (of persons) is not truly existent.</p></li>
<li><p>Whether non-self phenomena are truly existent from its own side or not, is (probably) not important towards the path to the end of suffering. (See the <a href="https://en.wikipedia.org/wiki/Parable_of_the_Poisoned_Arrow" rel="nofollow noreferrer">Parable of the Poisoned Arrow</a>, <a href="https://www.accesstoinsight.org/tipitaka/sn/sn56/sn56.031.than.html" rel="nofollow noreferrer">Parable of the Simsapa Leaves</a> and the <a href="https://www.accesstoinsight.org/tipitaka/an/an04/an04.077.than.html" rel="nofollow noreferrer">Discourse on the Unconjecturables</a>)</p></li>
</ol>

<p>Of course, there may be a lot of Theravadins out there who dispute my second statement above, and would assert that all non-self phenomena are truly existent from its own side.</p>

<p>EDIT: Just to make it clearer:</p>

<p>All sankharas (conditioned and/or compounded things) are subject to change, arising and passing. Nibbana is not subject to change, arising and passing. Both sankharas and nibbana are empty of a self. But this does not mean that sankharas and nibbana are not truly existent. The self is definitely an illusion, but the world, transient as it is, may not be an illusion. Whether the world is an illusion or not, is not important to the path to the end of suffering (according to Theravada, in my opinion).</p>
