Utpaladeva (c. 900–950 C.E.) was the chief originator of the Pratyabhijñā philosophical theology of monistic Kashmiri Śaivism, which was further developed by Abhinavagupta (c. 950–1020 C.E.) and other successors. The Ajaḍapramātṛsiddhi, “Proof of a Sentient Knower,” is one component of Utpaladeva’s trio of specialized studies called the Siddhitrayī, “Three Proofs.” This article provides an introduction to and translation of the Ajaḍapramātṛsiddhi along with the Vṛtti commentary on it by the nineteenth–twentieth century paṇḍit, Harabhatta Shastri. Utpaladeva in this work presents “transcendental” (...) arguments that a universal knower (pramātṛ), the God Śiva, necessarily exists and that this knower is sentient (ajaḍa). He defends the Pratyabhijñā understanding of sentience against alternative views of both Hindu and Buddhist schools. As elsewhere in his corpus, Utpaladeva also endeavors through his arguments to lead students to the recognition (pratyabhijñā) of identity with Śiva, properly understood as the sentient knower. (shrink)