user471: What is the difference between the concept of emptiness (Śūnyatā in Sanskrit, or suññatā in Pali) in the Theravada tradition and the concept of emptiness in the Mahayana tradition?
From my basic understanding, Theravada emptiness is only regarding the self, while Mahayana emptiness is regarding all things. Is this true?
Or does Theravada also teach the emptiness of all things (e.g. in the sutta about foam and bubbles)?
Are these (Theravada emptiness and Mahayana emptiness) really completely different, or at some level, do they allude to the same thing?
For Theravada, could it be, that the emptiness of self is important for the path to ending suffering, but the emptiness of all things is not important for the path to ending suffering (as per the Parable of the Poisoned Arrow and the Parable of the Leaves in the Forest)?
I found the following quote from this answer interesting:

It is said that beginner practitioners ("hinayana") only understand
  corelessness of beings (anatta), but still assume various stuff to be
  objectively/ontologically existing. This results in them erroneously
  reifying such concepts as the five skandhas, 12 nidanas, 4 noble
  truths, nirvana, and enlightenment. Advanced practitioners
  ("mahayana") clearly understand that all knowable phenomena without
  exception are contextually defined composites.


user8157: Emptiness in Pali refers to 'empty of self & anything pertaining to/belonging to self' (SN 35.85).
Mahayana argues things are empty of independent existence because they are dependent on causes & conditions. Mahayana says dependent origination is emptiness but this does not match the Pali because, in Pali, dependent origination explains the arising of suffering. 
The Mahayana is different to the Pali because, in Pali, Nirvana is not dependent on causes & conditions but Nirvana is empty. In Pali, everything is empty (of self) when seeing clearly. It is not required to discern causes & conditions. This is why SN 35.85 states the sense spheres are empty, without going into any other explanation.
The sutta about foam (Phena Sutta) is not about emptiness (sunnata). It is best to read a proper translation of it, such as Bhikkhu Bodhi's at Sutta Central.
Mayahana ideas about emptiness are only intellectual and not meditative because, in Pali or meditation, phenomena arise according to their function. While consciousness, for example, is impermanent & arises & ceases based on causes & conditions, whenever consciousness functions, it performs the function of consciousness, namely, seeing, hearing, tasting, touching, smelling & cognising. Consciousness, when it functions, is always consciousness. Consciousness is never empty of being consciousness. Thus the Pali teaches: "Why do you call it consciousness? Because it cognises, thus it is called consciousness" (MN 43; SN 22.79). 
To believe consciousness really does not exist because it is dependent on neurons, atoms, electricity, sense organs, the body, etc, is merely intellectual and unrelated to meditation. In real meditation, consciousness is discerned as being consciousness but empty of self and also impermanent & dependent on sense bases. However, when consciousness arises, it functions as consciousness rather than is not consciousness or functions as something else. Consciousness is consciousness but is void of self because consciousness is sense awareness where as 'self' is a thought (sankhara aggregate). 
Mahayana ideas are the product of thinking rather than direct seeing. This Mahayana ideas should not even be labelled as "beginners" because they do not even arise from meditation but arise from reading books.

user13375: The following answer is informed by Insight into Emptiness by Khensur Jampa Tegchok who was a former abbot of Sera Je Monastery.
Presentation of Tenets
According to what is currently taught in contemporary Tibetan Buddhist monasteries, the view of selflessness differs between proponents of the Fundamental Vehicle school (which includes Theravada) and the Universal Vehicle school (or Mahayana). The common delineation is given as four different (ancient) tenet systems regarding selflessness:

Vaibhashika
Sautrantika
Chittamatra
Madhyamaka

The first two tenet systems belong to members of the Fundamental Vehicle school while the latter two are ascribed to the Universal Vehicle.
Here is a brief breakdown of the view of selflessness as it differs among these tenet systems:
Selflessness of persons (from course to subtle)

Emptiness of a permanent, unitary, and independent person
Emptiness of a self-sufficient, substantially existent person
Emptiness of an inherently existent person

Selflessness of phenomena

Emptiness of existing by its own characteristics as the basis or
referent of its name
Emptiness of the form and so forth and a valid cognizer of it being
different substances (different substantial entities)
Emptiness of true existence (existing without being posited by the
force of appearing to a nondefective consciousness)
Emptiness of inherent existence (existing from its own side,
existing by its own characteristics, and so on)

Definitions:

Permanent means something that does not change from one moment to the next
Impermanent means that something changes under the influences of causes and conditions
Unitary is something that is one seamless whole that has no parts
Independent has different definitions given different contexts:

Independent is something not being affected by or not relying upon causes and conditions
In the context of a person it means being independent of the aggregates as well
In Prasangika it means existing without depending on being merely imputed by name and concept

Self-sufficient means being able to exist independently in a
self-supporting manner, without depending on anything else, such as
the aggregates
Substantially existent person means being able to know such a person
exists without the appearance of the aggregates

In general, it is said that the Fundamental Vehicle systems do not subscribe to the selflessness of phenomena. Furthermore, the Vaibhashikas only subscribe to the lack of a permanent, unitary and independent person. That is they do believe that a self-sufficient, substantially existent person exists. The Sautrantikas on the other hand do not believe in a self-sufficient, substantially existent person nor do any of the other tenet systems.
All of that is to say, it is my understanding that the modern day Theravada is most closely aligned with the Sautrantika tenet system.

471: <p>What is the difference between the concept of emptiness (Śūnyatā in Sanskrit, or suññatā in Pali) in the Theravada tradition and the concept of emptiness in the Mahayana tradition?</p>

<p>From my basic understanding, Theravada emptiness is only regarding the self, while Mahayana emptiness is regarding all things. Is this true?</p>

<p>Or does Theravada also teach the emptiness of all things (e.g. in the <a href="http://www.accesstoinsight.org/tipitaka/sn/sn22/sn22.095.than.html" rel="nofollow noreferrer">sutta about foam and bubbles</a>)?</p>

<p>Are these (Theravada emptiness and Mahayana emptiness) really completely different, or at some level, do they allude to the same thing?</p>

<p>For Theravada, could it be, that the emptiness of self is important for the path to ending suffering, but the emptiness of all things is not important for the path to ending suffering (as per the <a href="https://en.wikipedia.org/wiki/Parable_of_the_Poisoned_Arrow" rel="nofollow noreferrer">Parable of the Poisoned Arrow</a> and the <a href="http://www.accesstoinsight.org/tipitaka/sn/sn56/sn56.031.than.html" rel="nofollow noreferrer">Parable of the Leaves in the Forest</a>)?</p>

<p>I found the following quote from <a href="https://buddhism.stackexchange.com/a/3863/471">this answer</a> interesting:</p>

<blockquote>
  <p>It is said that beginner practitioners ("hinayana") only understand
  corelessness of beings (anatta), but still assume various stuff to be
  objectively/ontologically existing. This results in them erroneously
  reifying such concepts as the five skandhas, 12 nidanas, 4 noble
  truths, nirvana, and enlightenment. Advanced practitioners
  ("mahayana") clearly understand that all knowable phenomena without
  exception are contextually defined composites.</p>
</blockquote>
 8157: <p>Emptiness in Pali refers to '<em>empty of self &amp; anything pertaining to/belonging to self</em>' (SN 35.85).</p>

<p>Mahayana argues things are empty of independent existence because they are dependent on causes &amp; conditions. Mahayana says dependent origination is emptiness but this does not match the Pali because, in Pali, dependent origination explains the arising of suffering. </p>

<p>The Mahayana is different to the Pali because, in Pali, Nirvana is not dependent on causes &amp; conditions but Nirvana is empty. In Pali, everything is empty (of self) when seeing clearly. It is not required to discern causes &amp; conditions. This is why SN 35.85 states the sense spheres are empty, without going into any other explanation.</p>

<p>The sutta about foam (Phena Sutta) is not about emptiness (sunnata). It is best to read a proper translation of it, such as Bhikkhu Bodhi's at Sutta Central.</p>

<p>Mayahana ideas about emptiness are only intellectual and not meditative because, in Pali or meditation, phenomena arise according to their function. While consciousness, for example, is impermanent &amp; arises &amp; ceases based on causes &amp; conditions, whenever consciousness functions, it performs the function of consciousness, namely, seeing, hearing, tasting, touching, smelling &amp; cognising. Consciousness, when it functions, is always consciousness. Consciousness is never empty of being consciousness. Thus the Pali teaches: "<em>Why do you call it consciousness? Because it cognises, thus it is called consciousness</em>" (MN 43; SN 22.79). </p>

<p>To believe consciousness really does not exist because it is dependent on neurons, atoms, electricity, sense organs, the body, etc, is merely intellectual and unrelated to meditation. In real meditation, consciousness is discerned as being consciousness but empty of self and also impermanent &amp; dependent on sense bases. However, when consciousness arises, it functions as consciousness rather than is not consciousness or functions as something else. Consciousness is consciousness but is void of self because consciousness is sense awareness where as 'self' is a thought (sankhara aggregate). </p>

<p>Mahayana ideas are the product of thinking rather than direct seeing. This Mahayana ideas should not even be labelled as "beginners" because they do not even arise from meditation but arise from reading books.</p>
 13375: <p>The following answer is informed by <a href="https://rads.stackoverflow.com/amzn/click/B008YFZBCK" rel="nofollow noreferrer">Insight into Emptiness</a> by Khensur Jampa Tegchok who was a <a href="https://fpmt.org/mandala/archives/mandala-for-2015/july/the-life-of-khensur-jampa-tegchok/" rel="nofollow noreferrer">former abbot of Sera Je Monastery.</a></p>

<p><strong>Presentation of Tenets</strong></p>

<p>According to what is currently taught in contemporary Tibetan Buddhist monasteries, the view of selflessness differs between proponents of the Fundamental Vehicle school (which includes Theravada) and the Universal Vehicle school (or Mahayana). The common delineation is given as four different (ancient) tenet systems regarding selflessness:</p>

<ol>
<li>Vaibhashika</li>
<li>Sautrantika</li>
<li>Chittamatra</li>
<li>Madhyamaka</li>
</ol>

<p>The first two tenet systems belong to members of the Fundamental Vehicle school while the latter two are ascribed to the Universal Vehicle.</p>

<p>Here is a brief breakdown of the view of selflessness as it differs among these tenet systems:</p>

<p><strong>Selflessness of persons (from course to subtle)</strong></p>

<ol>
<li>Emptiness of a permanent, unitary, and independent person</li>
<li>Emptiness of a self-sufficient, substantially existent person</li>
<li>Emptiness of an inherently existent person</li>
</ol>

<p><strong>Selflessness of phenomena</strong></p>

<ol start="4">
<li><p>Emptiness of existing by its own characteristics as the basis or
referent of its name</p></li>
<li><p>Emptiness of the form and so forth and a valid cognizer of it being
different substances (different substantial entities)</p></li>
<li><p>Emptiness of true existence (existing without being posited by the
force of appearing to a nondefective consciousness)</p></li>
<li><p>Emptiness of inherent existence (existing from its own side,
existing by its own characteristics, and so on)</p></li>
</ol>

<p><strong>Definitions:</strong></p>

<ul>
<li><p><em>Permanent</em> means something that does not change from one moment to the next</p></li>
<li><p><em>Impermanent</em> means that something changes under the influences of causes and conditions</p></li>
<li><p><em>Unitary</em> is something that is one seamless whole that has no parts</p></li>
<li><p><em>Independent</em> has different definitions given different contexts:</p>

<ol>
<li>Independent is something not being affected by or not relying upon causes and conditions</li>
<li>In the context of a person it means being independent of the aggregates as well</li>
<li>In Prasangika it means existing without depending on being merely imputed by name and concept</li>
</ol></li>
<li><p><em>Self-sufficient</em> means being able to exist independently in a
self-supporting manner, without depending on anything else, such as
the aggregates</p></li>
<li><p><em>Substantially existent</em> person means being able to know such a person
exists without the appearance of the aggregates</p></li>
</ul>

<p>In general, it is said that the Fundamental Vehicle systems do not subscribe to the selflessness of phenomena. Furthermore, the Vaibhashikas only subscribe to the lack of a permanent, unitary and independent person. That is they <em>do</em> believe that a self-sufficient, substantially existent person exists. The Sautrantikas on the other hand do not believe in a self-sufficient, substantially existent person nor do any of the other tenet systems.</p>

<p>All of that is to say, it is my understanding that the modern day Theravada is most closely aligned with the Sautrantika tenet system.</p>
