Precepts of Conduct and Precepts of Doctrine

In Paul William’s book “Mahayana Buddhism: The Doctrinal Foundations” he posits that the early sangha was united by a vinaya that had little to do with doctrine. So two members of the sangha could both consider each other Buddhists in good standing because they both kept the vinaya, but disagree on doctrine.

In a sense, doctrine underlies all the precepts. That isn’t the point. The point here is that some precepts are very specific about doctrine. The BNS specifically mentions doctrine in many places:

8th minor – Do not be anti-Mahayanaist
34, 35-Vows and pledges
And all the precepts that mention hinayana, pratekyabuddha and sravaka references (roughly Theravadism, solitary Buddhism and beggar’s Buddhism)

Options
1) This ancient doctrinal argument is valid and worth pressing forward today.
2) This ancient dispute is no longer relevant
3) The specific doctrines should be reinterpreted.

Example
I’m going to interpret this as an exhortation to figure out what is the “state of the art” in doctrine and keep to that. At the time of the BNS, Mahayana Buddhism was the state of the art and I think, if these precepts aren’t just simple minded boosterism, these precepts were exhorting people to see the Dharma as something that we are getting better at understanding and isn’t a fixed think that is so well understood that no innovation or adaptation is possible.