If all phenomena are fabricated and, at the same time, are fabrications.
The set of all phenomena(things that can be felt/percieved/cognized) is smaller than the set of sankharas.
What are those sankharas that lie outside of what can be felt/percieved/cognized? (excluding the phenomena of the designation of the non-phenomena)
"It may happen, Ananda, that Wanderers of other sects will be saying this: ‘The recluse Gotama speaks of the Cessation of Perception and Feeling and describes it as pleasure. What is this (pleasure) and how is this (a pleasure)?’
“Those who say so, should be told: ‘The Blessed One describes as pleasure not only the feeling of pleasure. But a Tathagata describes as pleasure whenever and whereinsoever it is obtained.’”
—Majjhima Nikaya 59
Whenever any level of conditioned phenomena is overcome, a pleasant state is recognized simply by virtue of contrast (Anguttara Nikaya 9.34). Contrast recognition is a necessary skill throughout the path.
“the property of light is discerned in dependence on darkness.”
I am not even sure that we could agree that there are 2 types of unknown:
The unknown that we know that we don’t know.
The unknown that we don’t know that we don’t know.
Anyway, from there:
For the 1st type: I can take examples: “The beginning of Saṃsāra”, “The Buddha-range”, “The precise working of out of result of kamma”, “The jhana-range” as in AN4.77
For the 2nd type: I can take an example: The siṁsapā forest mentioned in SN56.31