So does the Mahayana undermine the 4 Noble Truths?
The Heart Sutra may be the most commonly chanted Buddhist text. In English, it is less than 300 words long.
Halfway through is the astonishing claim that there is “no truth of suffering, of the cause of suffering, of the cessation of suffering nor of the path” — in effect denying the Four Noble Truths that the Buddha himself taught.
So here is a Buddhist text that seems to undermine the very foundation of Buddhism. I know of no parallel text in any other religion.
But Buddhism, at least in theory, is based on undermining itself. It is an ancient post-modernism, calling into question any description of reality, including its own, because humans crave descriptions of reality more than reality itself.