Pratītyasamutpāda and the two truths: when I distinguish saṃvṛti-satya (conventional truth) from paramārtha-satya (ultimate truth), am I positing two ontologies, or two modes of approach to one dependently-arisen reality?

Nāgārjuna, answered from the texts and cited to the page.

The position in brief

Two truths describe one reality at two levels of analysis, not two ontologies. Saṃvṛti-satya is "covering" or conventional truth — the level at which ordinary discourse, action, ethical practice, and the teaching of the dharma all proceed. Paramārtha-satya is ultimate truth — the level at which the same reality is seen as empty of intrinsic nature.1

The two are inseparable: MMK 24.10, "Without dependence on the conventional, the ultimate cannot be taught; without recourse to the ultimate, nirvāṇa is not attained." The structure is functional and pedagogical, not the positing of an additional metaphysical realm above the conventional. Pratītyasamutpāda is what unifies them: dependent origination is what emptiness means (MMK 24.18), and both truths describe phenomena that arise dependently.23

Sources

  1. Therefore, there is only frustration and hindrance (of understanding). dve satye samupaéritya buddhanam dharmadegana/ lokasamvrtisatyam ca satyam ca paramarthatah// The teaching of the の by 'the various Buddhas is based on the two truths; namely, the relative (worldly) truth and the absolute (supreme) truth.
    Mulamadhyamakakarika, pp. 154–156
  2. Thus, But doing the opposite, you easily remain (without falling into extremes). 6 (Anything that arises from) a collection of causes and conditions, or is a collection of many parts, is necessarily oppositionally posited. Its lack of independence and autonomy is the evidence due to which you said that the interdependent is (necessarily) empty.
    The Precious Garland - Ratnavali, pp. 95–99
  3. For the verse ef MM, wt, 9. C. fom yaumde to tari tamah inclusive, + Rom arn. "Rom. air, 1 R substrates yat for nam. omits evam; which C has. 3 R puta tah a the end of next sentence, but T shows question and C has no egtive, that the text reading lone mets dhe eae pratieraa, R.
    The Dialectical Method - Vigrahavyavartani, pp. 98–99

Where the argument is made

  • MMK Chapter 24 entire, especially 24.8-10 on the two truths ('Without dependence on the conventional, the ultimate cannot be taught
  • without recourse to the ultimate, nirvāṇa is not attained')
  • MMK 24.18 — yaḥ pratītyasamutpādaḥ śūnyatāṃ tāṃ pracakṣmahe — the unifying verse
  • Pratītyasamutpādahṛdayakārikā (the short treatise on the heart of dependent origination)
  • Ratnāvalī Chapter 1 on the relation between conventional ethical practice and ultimate analysis
  • Śūnyatāsaptati on the dependent arising of dharmas

How the argument was received

The two-truths doctrine is the structural backbone of the Madhyamaka and has been articulated by every Madhyamaka commentator from Buddhapālita through Candrakīrti and Bhāviveka into the Tibetan traditions. The position has held without retraction. Later Tibetan scholastic debates (Gelug's non-affirming-negation reading via Tsongkhapa, Nyingma/Sakya/Kagyu's affirming-negation readings) refine the formal structure in ways that go beyond what my verses themselves settle; I am the foundation, not the settler of those refinements.