APA: Uspenskiĭ, P. D. (2001). In search of the miraculous : fragments of an unknown teaching (New edition). Harcourt, Inc.
Link: https://search.worldcat.org/en/title/47183414
Page 38: quotation attributed to G.I. Gurdjieff:
There are periods in the life of humanity, which generally coincide with the beginning of the fall of cultures and civilizations, when the masses irretrievably lose their reason and begin to destroy everything that has been created by centuries and millenniums of culture. Such periods of mass madness, often coinciding with geological cataclysms, climatic changes, and similar phenomena of a planetary character, release a very great quantity of the matter of knowledge. This, in its turn, necessitates the work of collecting this matter of knowledge which would otherwise be lost. Thus the work of collecting scattered matter of knowledge frequently coincides with the beginning of the destruction and fall of cultures and civilizations.
Some information about the source:
In Search of the Miraculous by Peter Deminaovich Ouspensky GEORGE GURDJIEFF’S EARLY LECTURES RETOLD BY PETER OUSPENSKY
In Search of the Miraculous tops the list of Gurdjieff books even though it was not authored by Gurdjieff himself, as without it, Gurdjieff's teaching would have likely disappeared into obscurity. It is thanks to Peter Ouspensky's account of searching for the miraculous and crossing paths with Gurdjieff in Russia, that Gurdjieff's most powerful theories and methods survived to this day. The book was published posthumously, after its manuscript had been reviewed and praised by Gurdjieff, somewhat healing the decades-long rift between them. To this day, In Search of the Miraculous is the best-selling doorway into Gurdjieff's practical, theoretical and philosophical teachings.
More about this book here: In Search of the Miraculous