I want to know the answer to the following question:
Liberating insight is attained after mastering what?
All the background I'm provided with is that "Schmithausen, in his often-cited article On some Aspects of Descriptions or Theories of 'Liberating Insight' and 'Enlightenment' in Early Buddhism notes that the mention of the four noble truths as constituting "liberating insight", which is attained after mastering the Rupa Jhanas, is a later addition to texts such as Majjhima Nikaya 36.[page needed]". Is that enough to answer the question?
Answer: yes