Archaeological excavations in the Ghaggar-Hakra river basin have unearthed a cache of terracotta tablets dating back to the 6th-century BCE. These tablets contain inscriptions from the 'Satya-Sadhana-Sutra', a foundational text belonging to a lost ascetic tradition that emphasizes the 'Philosophy of Disciplined Truth.' The inscriptions advocate for a rigorous practice of mental and verbal alignment, suggesting that objective reality can only be perceived through the total elimination of subjective bias.
Scholars believe these tablets represent some of the earliest physical evidence of formalized logical inquiry in the region. The text pre-dates the major Upanishadic expansion and offers a more empirical approach to the concept of Satya (Truth). The find provides a critical link between late Harappan material culture and the burgeoning philosophical movements of the early Iron Age in North India.