This chapter offers an outline of Vasil'ev's life and works, especially of his activities as a historian and man of letters. Vasil'ev grew up in a stimulating, highly cultured family environment. Already as a boy, he showed interest in literature and during his university years, while studying medicine, he also dedicated himself to poetry by publishing a collection of lyrics, Longing for Eternity (1904). Such poems constitute a first step towards imaginary logic. Later, Vasil'ev enrolled in the Faculty of Philology and History at the University of Kazan and in 1906 he discussed a thesis on history, although he continued to deal with poetry and literature (Verhaeren, Swinburne, Gogol). Between 1908 and 1913 he developed his logical ideas, spent two study stays in Germany and began teaching at the University of Kazan. During these years, he published his major articles in logic. In 1912, in an essay on Tolstoy and Solovyov, he set forth his ethical conceptions. But with the outbreak of the First World War his life took a dramatic turn. In 1916, the first symptoms of that mental illness which was to afflict him for the rest of his life manifested themselves. In 1917 he was in Moscow during the October Revolution. In later years, mental breakdowns alternated with periods of teaching at the university, but in 1922 he was definitively interned in a psychiatric hospital where he remained until his death in 1940.