The historiosophical conception of P. Ya.Chaadayev, set out in the first philosophical letter, has had both its followers and opponents up to the present time. However, in the context of the emerging arguments, the topic raised by O. E. Mandelstam in his article “On the Nature of the Word” (1921–1922), has not yet been discussed. According to the poet, while creating his conception, Chaadayev did not take into acccount the Russian language, which is “not only the door to history, but history itself”. Mandelstam considers the Russian language to be “existential”, ontological, being able to “evolve into an event” and influence the spiritual and physical order of things. One of its qualities is “the idea of the reality of the word itself”. Thus, the poet proceeded not from the Saussurean idea of the sign arbitrariness (concept of the conditional, conventional nature of the word is based upon it), but from the recognition of the spiritual nature and unconventionality of the word, which goes back to the linguistic concepts of W. von Humboldt and A. A. Potebnya. The article shows that these conceptions of Mandelstam and his predecessors are close to the linguistic intuitions of N. V. Gogol, who is an antagonist of Chaadayev under these circumstances. Chaadayev's historiosophy is far from the word but Gogol's “Russian idea” is to a great extent based on it.