Through the work of Nagarjuna, the Mahayana movement developed the interpretation that physical matter is ‘empty’ of any substantiality. This is due to Nagarjuna applying his tetra lemma (catuskoti) formula to the assessment of the ‘Chain of Dependent Origination’ (Pratītyasamutpāda), and logically proving that just as the true enlightened state has no-self associated with it; then it is also equally true that physical matter has no substantiality associated with it. Everything is dependent upon everything else, conditioned by everything else, and contingent upon everything else.