into "fiery debates... in Sanskrit." He was expelled from the Oriental Institute in 1968. Piatigorsky continued to lecture at the University of Moscow. He pursued his Indological investigations, increasingly dealing with Buddhist thought, and continued with more general work on the metatheory of consciousness, psychology, semiotics and philosophy in general, while collaborating with various Russian philosophers and thinkers outside of Indology. Chief among them was his close friend, philosopher Merab Mamardashvili. Influenced by German Idealism, Mamardashvili was a Deputy Editor of the leading journal, Voprosy Filosofii ("Problems of Philosophy"), and was also a principal representative of the so-called "Moscow School of Methodology." Participants in the Moscow School seminars included: Alexander Zinoviev, Evald Ilyenkov, Georgy Shchedrovitsky, Boris Grushin, Lefebvre, and others. The School is believed by some to be the source of the most important developments in philosophy in the post-War period, rivaling anything done in the Western analytical tradition. The School remains virtually unknown in the West because its members were forced to operate behind the "Iron Curtain" in a context of severely reduced operational visibility and Soviet-style repression. One of his friends was also an indologist and culture theoretician David Zilberman, who in 1968–1972 was a postgraduate student working under prof. Yuri Levada. Together they used to discuss problems of consciousness development. After they both migrated they kept friendship and continued research co-operation till Zilberman's death in July 1977. Piatigorsky's book" Myshlenie i nablyudenie" (Thinking and Observation), published in Riga in 2002, was dedicated to David Zilberman and included an explicit confession of Zilberman's influence on the author's thought. In 1972, Piatigorsky's Buddhist teacher Dandaron was arrested by Soviet authorities. A number of Dandaron's students were imprisoned. Dandaron was sent to a Soviet labor camp where he perished in 1974. During the same period, Mamardashvili and Piatigorsky co-authored: "Symbol and Consciousness: Metaphysical Discussion of Consciousness, Symbolism and Language" Jerusalem (1982), in Russian. This abstract and complex text, combining Western and Eastern terms, is considered by some to be the most significant philosophical work written in the Russian language. The text: Written in the two years before Piatigorsky left the Soviet Union for Britain in 1974, the manuscript was spirited out of the country by the British-Czech social philosopher Ernest Gellner. It is worth noticing that the text was written in a deteriorating situation of renewed political repression of the Russian intelligentsia by the Soviet state. The 'tightening of restrictions'