user-1: I remember reading, in the 1st book I picked up on Buddhism, that it was a synergetic religion, literally, that it combines with (I suppose indigenous) traditions, such as the tao, and bon.
Did the Buddha ever talk about this aspect of (what has ended up as) his teachings?
Are there any interesting studies or way of thinking about Buddhism in those terms, general to all that it has taken up and made its own?

user-1: The Buddha clearly identified his dharma as something that both transcends and complements religion, including teachers, rules, lifestyles, and ethics. He specifically invites his hearers to remain associated with whatever religion they have inherited, and implies that the dharma is perfectly compatible with all of this. See, for example, 

"…you may think: ‘the ascetic Gotama says this in order to get
  disciples.’ But you should not regard it like that. Let him who is
  your teacher remain your teacher. Or you may think: ‘He wants us to
  abandon our rules.’ Let your rules remain as they are. Or you may
  think: ‘He wants us to abandon our way of life.’ But you should not
  regard it like that. Let your way of life remain as it was. Or you may
  think: ‘He wants to establish us in the doing of things that according
  to our teaching was wrong, and are so considered among us.’ But you
  should not regard it like that. Let those things you consider wrong
  continue to be so considered. Or you may think: ‘He wants to draw us
  away from things that according to our teaching are good, and are so
  considered among us.’ But you should not regard it like that. Let
  whatever you consider right continue to be so considered. Nigrodha, I
  do not speak for any of these reasons." (Digha Nikaya, sutta 25, para. 23; iii 56)

Elsewhere he tells a disciple who has converted from Jainism to continue to support the Jains with alms, and he disparages ethics, rules, and mere mechanical observances as inferior matters. He even warns against dogmatism, pointing out that dharma is beyond linguistic and rational categories.

-1: <p>I remember reading, in the 1st book I picked up on Buddhism, that it was a synergetic religion, literally, that it combines with (I suppose indigenous) traditions, such as the tao, and bon.</p>

<p>Did the Buddha ever talk about this aspect of (what has ended up as) his teachings?</p>

<p>Are there any interesting studies or way of thinking about Buddhism in those terms, general to all that it has taken up and made its own?</p>
 -1: <p>The Buddha clearly identified his dharma as something that both transcends and complements religion, including teachers, rules, lifestyles, and ethics. He specifically invites his hearers to remain associated with whatever religion they have inherited, and implies that the dharma is perfectly compatible with all of this. See, for example, </p>

<blockquote>
  <p>"…you may think: ‘the ascetic Gotama says this in order to get
  disciples.’ But you should not regard it like that. Let him who is
  your teacher remain your teacher. Or you may think: ‘He wants us to
  abandon our rules.’ Let your rules remain as they are. Or you may
  think: ‘He wants us to abandon our way of life.’ But you should not
  regard it like that. Let your way of life remain as it was. Or you may
  think: ‘He wants to establish us in the doing of things that according
  to our teaching was wrong, and are so considered among us.’ But you
  should not regard it like that. Let those things you consider wrong
  continue to be so considered. Or you may think: ‘He wants to draw us
  away from things that according to our teaching are good, and are so
  considered among us.’ But you should not regard it like that. Let
  whatever you consider right continue to be so considered. Nigrodha, I
  do not speak for any of these reasons." (Digha Nikaya, sutta 25, para. 23; iii 56)</p>
</blockquote>

<p>Elsewhere he tells a disciple who has converted from Jainism to continue to support the Jains with alms, and he disparages ethics, rules, and mere mechanical observances as inferior matters. He even warns against dogmatism, pointing out that dharma is beyond linguistic and rational categories.</p>
