I suggest that the original form of the ‘enlightenment’ set was the ‘basic’ set: idaṃ dukkhaṃ, ayaṃ dukkha-samudayo, ayaṃ dukkha-nirodho, ayaṃ dukkha-nirodha-gāminī paṭipadā When these items became known as “Truths”, they were [later] so designated: idaṃdukkha-saccaṃ, etc.