user6994: In the Majjhima Nikaya, there are mentions of Bodhisattvas.
For instance, Bhayabherava Sutta (4. Fear and Dread) says:


"Before my enlightenment, while I was still ony an unenlightened Bodhisatta..."


It is a sentence that is repeated throughout the MN.
The Acchariya-abbhuta Sutta (123. Wonderful and Marvellous) also says:

"Mindfull and fully aware, Ananda, the Bodhisatta appeared in the Tusita heaven."


I have two questions:

Are there Bodhisattva practices in Theravada? (such as the cultivation of Bodhicitta and the six perfections presented in Mahayana traditions)
Since we find occurrences in the Pali Canon, why do we often hear that the notion of bodhisattva is a late notion?


user10304: From general knowledge I gleaned the conventional Theravada appeared in the English world doesn't practice for Bodhisattva. They admit 7 Buddhas included the future Maitreya as the totality of all in eons of Kalpas plus endless spacetime/universes. The highest goal of conventional Theravada is not a Buddha - there is no chance/ only 7 Buddhas existed the last one has already been claimed by Maitreya - but Arahat, who ended sufferings by realized Nibbana.
Why the conventional Theravada said the Bodhisattva is a late notion, because the scholars said so. Like Saptha Visuddhi quoted Edward Conze in her/his whole post, Edward Conze's scholastic studies are equally as true as the Suttas, if not more scientifically correct with archaeological evidences!  
I didn't read Edward Conze, so I have no comment on Edward Conze's scholastic study however he laid hands on Mahayana didn't endorse him the authentic knowledge on the Mahayana teaching hence enabled him to conclude his conclusions. But by Saptha Visuddhi's interpretation of “Bodhisattva vow” if s/he derived her/his understanding from Edward Conze then it is wrong. Bodhisattva is already enlightened, but not entering Nirvana until all the beings are ferrying to the "other shore"/ free of suffering. It will take too long paragraph to explain for the English sect has too many wrong terms and wrong understandings. 
In 《解深密經》 the Buddha explaint when some Bodhisattvas seeing the horror of Naraka and other lower realms they were too horrified and could't endure Samsara anymore, they can choose to enter Nirvana, (I think these refer to the Hinayana sect's practice, need re-check the Sutra). But the higher level (esp. 8th level and above) will continuous to overcome those until reached perfect wisdom - Anuttara-samyak-sambodhi 等正覺, Buddha. 

user8044: Every reference that is ever made to a “Bodhisatta” in the Theravada Suttas is in relation to the Present Supreme Buddha, or the six other Buddhas that appeared in the last 91 aeons. Thus the Bodhisatta ideal is the sphere or domain (vishaya) of the seven Buddha that has appeared  and the One yet  to come.
Edward Conze was a Mahayana scholar, translated the Mahayana Prajnaparamita or Perfection of Wisdom sutras from original Sanskrit to English.  In the words of Edward Conze:

” “……About 100 BCE (roughly 400 years after the Buddha’s  Parinibbana) a number of Buddhists in India felt that the existing statements of the doctrine had become stale and useless. In the conviction that Dhamma required ever new re-formulations so as to meet the needs of new ages, new populations and new social circumstances, they set out to produce new literature which ultimately came to known as Mahayana Buddhism. The creation of this literature is one of the most significant outbursts of creative energy known to human history and it was sustained for about four to five centuries. Repetition alone, they believed, cannot sustain a living religion. Unless counterbalanced by constant innovation, it will become fossilized and lose its life-giving qualities, they believed”.

There are five doctrinal “innovations” of the Mahayanists that have been listed by Edward Conze. They are:

•  As concerns the goal there is a shift from the Arahant-ideal to the Bodhisattva-ideal;
  •   A new way of salvation is worked out, in which compassion ranks equal with wisdom, and which is marked by the gradual advance through six “perfections” (paramita);
  •   Faith is given a new range by being provided with a new pantheon of deities, or rather of persons more than divine;
  •   “Skill in means” (upayakausalya), an entirely new virtue, becomes essential to the saint, and is placed even above wisdom, the highest virtue so far;
  •   A coherent ontological doctrine is worked out, dealing with such items as “Emptiness”, “Suchness”, etc”.   

The oath in most Mahayana traditions to, “not to seek Enlightenment until ALL BEINGS ARE READY for Enlightenment” is the most visible contradiction to that of Theravada. The first thing one is supposed to do in becoming a “Mahayana Buddhist” is to take the “Bodhisattva vow”:They say each being should endeavor to become a Buddha i.e., each person should become a Bodhisattva. The historical timeline of the rise of Mahayana is discussed in detail by Edward Conze in his book,  “A Short History of Buddhism” (1980). According to Conze, the history of Buddhism can be conveniently divided into four periods:

•  The old Buddhism, which largely coincided with what later came to be known as Theravada
  •   Rise of Mahayana,
  •   Rise of the Tantra (Vajryana) and Ch’an (Zen),
  •   No further divisions.   


user-1: 
Since we find occurrences in the Pali Canon, why do we often hear that the notion of bodhisattva is a late notion?

It seems to me, practices for bodhisattva are mostly (or fully?) absent, and don't find nearly as much encouragement in the Nikayas/Agamas from the Buddha (or no encouragement at all? I don't recall reading any sutta where he would inspire anyone to do it). So, even though these texts refer to bodhisattvas, I guess there isn't really an actual practical path there or fully developed motivation for it, to become an ideal. But the idea that this is something one can do is there and I've read about ancient non-mahayanists taking that goal for themselves.
One related study on this is Bhikkhu Analayo's The Genesis of the Bodhisattva Ideal.

user701: Bodhisatta practices in Theravada are mentioned in Buddhavamsa, Jataka and Apadana atthakatha, especially in Visuddhajanavilāsiniyā, Apadana Atthakatha, the commentary of Apadana, which is believed to be a late addition to the Pali Canon, added after the Second and Third Buddhist Councils. This is probably why we hear that the notion of bodhisatta is a late addition. However, in Theravada countries like Sri Lanka where I come from, the bodhisattas are widely accepted. (See also the wikipedia section on Theravada bodhisattas. https://en.wikipedia.org/wiki/Bodhisattva)
According to Buddhavagga section in Apadana Atthakathaa, Theravada Buddhism has ten perfections dasapāramitā (Giving, morality, renunciation, wisdom, energy, patience, truthfulness, determination, loving kindness and equanimity)
and there are three types of bodhisattas, the ones aspiring to be Sammāsambuddha, Pacceka Buddha (a private Buddha) and Savaka Buddha (arahant).
According to the section Buddhavagga in Apadana Atthakathaa, to become a Sammāsambuddha, one requires either 4x10^140 (cattāri asaṅkhyeyyāni), 8x10^140 (aṭṭha asaṅkhyeyyāni) or 16x10^140 (soḷasa asaṅkhyeyyāni) eons of pāramitā perfection 

‘‘buddhānaṃ, bhante, patthanā kīva ciraṃ vaṭṭatī’’ti. Buddhānaṃ,
  ānanda, heṭṭhimaparicchedena cattāri asaṅkhyeyyāni
  kappasatasahassañca, majjhimaparicchedena aṭṭha asaṅkhyeyyāni
  kappasatasahassañca, uparimaparicchedena soḷasa asaṅkhyeyyāni
  kappasatasahassañca
  Apadana Atthakathaa

depending on whether he has high wisdom (Paññādhika), faith (Saddhādhika) or effort (Vīriyādhika).

Ete ca bhedā paññādhikasaddhādhikavīriyādhikānaṃ vasena ñātabbā.
  Paññādhikānañhi saddhā mandā hoti, paññā tikkhā. Saddhādhikānaṃ paññā
  majjhimā hoti, saddhā tikkhā. Vīriyādhikānaṃ saddhā paññā mandā hoti,
  vīriyaṃ tikkhanti.
Apadana Atthakathaa

A bodhisatta aspiring to be a pacceka buddha requires 2x10^140 (dve asaṅkhyeyyāni) eons of practice.

paccekabuddho paccekabodhisattabhūmiṃ ogāhanto dve asaṅkhyeyyāni
  kappasatasahassañca pāramiyo pūretvā
Apadana Atthakathaa

For an arahant a time limit is not given for the bodhisatta period.

6994: <p>In the Majjhima Nikaya, there are mentions of Bodhisattvas.</p>

<p>For instance, <em>Bhayabherava Sutta</em> (4. Fear and Dread) says:</p>

<blockquote>
  <ol start="3">
  <li>"Before my enlightenment, while I was still ony an unenlightened Bodhisatta..."</li>
  </ol>
</blockquote>

<p>It is a sentence that is repeated throughout the MN.</p>

<p>The <em>Acchariya-abbhuta Sutta</em> (123. Wonderful and Marvellous) also says:</p>

<blockquote>
  <p>"Mindfull and fully aware, Ananda, the Bodhisatta appeared in the Tusita heaven."</p>
</blockquote>

<p><br>
I have two questions:</p>

<ol>
<li>Are there Bodhisattva practices in Theravada? (such as the cultivation of Bodhicitta and the six perfections presented in Mahayana traditions)</li>
<li>Since we find occurrences in the Pali Canon, why do we often hear that the notion of bodhisattva is a late notion?</li>
</ol>
 10304: <p>From general knowledge I gleaned the <em>conventional</em> Theravada appeared in the English world doesn't practice for Bodhisattva. They admit 7 Buddhas included the future Maitreya as the totality of all in eons of Kalpas plus endless spacetime/universes. The highest goal of <em>conventional</em> Theravada is not a Buddha - there is no chance/ only 7 Buddhas existed the last one has already been claimed by Maitreya - but Arahat, who ended sufferings by realized Nibbana.</p>

<p>Why the <em>conventional</em> Theravada said the Bodhisattva is a late notion, because the scholars said so. Like Saptha Visuddhi quoted Edward Conze in her/his whole post, Edward Conze's scholastic studies are equally as true as the Suttas, if not more scientifically correct with archaeological evidences!  </p>

<p>I didn't read Edward Conze, so I have no comment on Edward Conze's scholastic study however he laid hands on Mahayana didn't endorse him the authentic knowledge on the Mahayana teaching hence enabled him to conclude his conclusions. But by Saptha Visuddhi's interpretation of “Bodhisattva vow” if s/he derived her/his understanding from Edward Conze then it is wrong. <strong>Bodhisattva is already enlightened, but not entering Nirvana until all the beings are ferrying to the "other shore"/ free of suffering</strong>. It will take too long paragraph to explain for the English sect has too many wrong terms and wrong understandings. </p>

<p>In 《解深密經》 the Buddha explaint when some Bodhisattvas seeing the horror of Naraka and other lower realms they were too horrified and could't endure Samsara anymore, they can choose to enter Nirvana, (I think these refer to the Hinayana sect's practice, need re-check the Sutra). But the higher level (esp. 8th level and above) will continuous to overcome those until reached perfect wisdom - Anuttara-samyak-sambodhi 等正覺, Buddha. </p>
 8044: <p>Every reference that is ever made to a “Bodhisatta” in the Theravada Suttas is in relation to the Present Supreme Buddha, or the six other Buddhas that appeared in the last 91 aeons. Thus the Bodhisatta ideal is the sphere or domain (vishaya) of the seven Buddha that has appeared  and the One yet  to come.</p>

<p><strong><a href="https://en.wikipedia.org/wiki/Edward_Conze" rel="nofollow noreferrer">Edward Conze was a Mahayana scholar</a></strong>, translated the Mahayana Prajnaparamita or Perfection of Wisdom sutras from original Sanskrit to English.  In the words of Edward Conze:</p>

<blockquote>
  <p>” “……About 100 BCE (roughly 400 years after the Buddha’s  Parinibbana) a number of Buddhists in India felt that the existing statements of the doctrine had become stale and useless. In the conviction that Dhamma required ever new re-formulations so as to meet the needs of new ages, new populations and new social circumstances, they set out to produce new literature which ultimately came to known as Mahayana Buddhism. The creation of this literature is one of the most significant outbursts of creative energy known to human history and it was sustained for about four to five centuries. Repetition alone, they believed, cannot sustain a living religion. Unless counterbalanced by constant innovation, it will become fossilized and lose its life-giving qualities, they believed”.</p>
</blockquote>

<p>There are five doctrinal “innovations” of the Mahayanists that have been listed by Edward Conze. They are:</p>

<blockquote>
  <p>•  As concerns the goal there is a shift from the Arahant-ideal to the Bodhisattva-ideal;<br>
  •   A new way of salvation is worked out, in which compassion ranks equal with wisdom, and which is marked by the gradual advance through six “perfections” (paramita);<br>
  •   Faith is given a new range by being provided with a new pantheon of deities, or rather of persons more than divine;<br>
  •   “Skill in means” (upayakausalya), an entirely new virtue, becomes essential to the saint, and is placed even above wisdom, the highest virtue so far;<br>
  •   A coherent ontological doctrine is worked out, dealing with such items as “Emptiness”, “Suchness”, etc”.   </p>
</blockquote>

<p>The oath in most Mahayana traditions to, “not to seek Enlightenment until ALL BEINGS ARE READY for Enlightenment” is the most visible contradiction to that of Theravada. The first thing one is supposed to do in becoming a “Mahayana Buddhist” is to take the “Bodhisattva vow”:They say each being should endeavor to become a Buddha i.e., each person should become a Bodhisattva. The historical timeline of the rise of Mahayana is discussed in detail by Edward Conze in his book,  “A Short History of Buddhism” (1980). According to Conze, the history of Buddhism can be conveniently divided into four periods:</p>

<blockquote>
  <p>•  The old Buddhism, which largely coincided with what later came to be known as Theravada<br>
  •   Rise of Mahayana,<br>
  •   Rise of the Tantra (Vajryana) and Ch’an (Zen),<br>
  •   No further divisions.   </p>
</blockquote>
 -1: <blockquote>
  <p>Since we find occurrences in the Pali Canon, why do we often hear that the notion of bodhisattva is a late notion?</p>
</blockquote>

<p>It seems to me, practices for bodhisattva are mostly (or fully?) absent, and don't find nearly as much encouragement in the Nikayas/Agamas from the Buddha (or no encouragement at all? I don't recall reading any sutta where he would inspire anyone to do it). So, even though these texts refer to bodhisattvas, I guess there isn't really an actual practical path there or fully developed motivation for it, to become an <em>ideal</em>. But the idea that this is something one can do is there and I've read about ancient non-mahayanists taking that goal for themselves.</p>

<p>One related study on this is Bhikkhu Analayo's <a href="https://www.buddhismuskunde.uni-hamburg.de/pdf/5-personen/analayo/genesis-bodhisattva.pdf" rel="nofollow noreferrer">The Genesis of the Bodhisattva Ideal</a>.</p>
 701: <p>Bodhisatta practices in Theravada are mentioned in <em>Buddhavamsa, Jataka</em> and <em>Apadana atthakatha</em>, especially in <em>Visuddhajanavilāsiniyā, Apadana Atthakatha</em>, the commentary of Apadana, which is believed to be a <a href="http://www.accesstoinsight.org/tipitaka/kn/index.html#ap" rel="nofollow noreferrer">late</a> addition to the Pali Canon, added after the Second and Third Buddhist Councils. This is probably why we hear that the notion of bodhisatta is a late addition. However, in Theravada countries like Sri Lanka where I come from, the bodhisattas are widely accepted. (See also the wikipedia section on Theravada bodhisattas. <a href="https://en.wikipedia.org/wiki/Bodhisattva" rel="nofollow noreferrer">https://en.wikipedia.org/wiki/Bodhisattva</a>)</p>

<p>According to <em>Buddhavagga</em> section in <em>Apadana Atthakathaa</em>, Theravada Buddhism has ten perfections <a href="http://tipitaka.org/romn/cscd/s0510a.att1.xml" rel="nofollow noreferrer"><em>dasapāramitā</em></a> (Giving, morality, renunciation, wisdom, energy, patience, truthfulness, determination, loving kindness and equanimity)
and there are three types of bodhisattas, the ones aspiring to be <em>Sammāsambuddha</em>, <em>Pacceka Buddha</em> (a private Buddha) and <em>Savaka Buddha</em> (arahant).</p>

<p>According to the section <em>Buddhavagga</em> in <em>Apadana Atthakathaa</em>, to become a Sammāsambuddha, one requires either 4x10^140 (<em>cattāri asaṅkhyeyyāni</em>), 8x10^140 (<em>aṭṭha asaṅkhyeyyāni</em>) or 16x10^140 (<em>soḷasa asaṅkhyeyyāni</em>) eons of <em>pāramitā</em> perfection </p>

<blockquote>
  <p>‘‘buddhānaṃ, bhante, patthanā kīva ciraṃ vaṭṭatī’’ti. Buddhānaṃ,
  ānanda, heṭṭhimaparicchedena cattāri asaṅkhyeyyāni
  kappasatasahassañca, majjhimaparicchedena aṭṭha asaṅkhyeyyāni
  kappasatasahassañca, uparimaparicchedena soḷasa asaṅkhyeyyāni
  kappasatasahassañca
  <a href="http://tipitaka.org/romn/cscd/s0510a.att1.xml" rel="nofollow noreferrer">Apadana Atthakathaa</a></p>
</blockquote>

<p>depending on whether he has high wisdom (<em>Paññādhika</em>), faith (<em>Saddhādhika</em>) or effort (<em>Vīriyādhika</em>).</p>

<blockquote>
  <p>Ete ca bhedā paññādhikasaddhādhikavīriyādhikānaṃ vasena ñātabbā.
  Paññādhikānañhi saddhā mandā hoti, paññā tikkhā. Saddhādhikānaṃ paññā
  majjhimā hoti, saddhā tikkhā. Vīriyādhikānaṃ saddhā paññā mandā hoti,
  vīriyaṃ tikkhanti.<br>
  <a href="http://tipitaka.org/romn/cscd/s0510a.att1.xml" rel="nofollow noreferrer">Apadana Atthakathaa</a></p>
</blockquote>

<p>A bodhisatta aspiring to be a pacceka buddha requires 2x10^140 (dve asaṅkhyeyyāni) eons of practice.</p>

<blockquote>
  <p>paccekabuddho <strong>paccekabodhisattabhūmiṃ</strong> ogāhanto dve asaṅkhyeyyāni
  kappasatasahassañca pāramiyo pūretvā<br>
  <a href="http://tipitaka.org/romn/cscd/s0510a.att1.xml" rel="nofollow noreferrer">Apadana Atthakathaa</a></p>
</blockquote>

<p>For an arahant a time limit is not given for the bodhisatta period.</p>
