The two levels of truth or reality in Madhyamaka philosophy, known as relative truth (saṃvṛti-satya) and absolute truth (paramārtha-satya). In many forms of Buddhism.the concept of two levels of truth concerned the validity of epistemological experience but in some forms of Mahāyāna it was also applied to matters of ontology. This is especially so in later Madhyamaka where saṃvṛti-satya applies to the mundane reality of saṃsāra and paramārtha-satya to the transcendental reality of enlightenment andnirvāṇa. The apparent hiatus between these two levels of reality or truth led to serious soteriological difficulties which generated much debate in later Mahāyāna concerning the relationship between these two forms of truth or reality. The relation between the two is discussed in treatises such as Jñānagarbha's Satyadvaya-vibhāga, where there is a tendency to identify them as two facets of the same phenomenon, neither identical nor different.