The book is devoted to the analysis of the connections of philosophical and scientific thought with the existential experience of a person, taken in his historical and cultural context. The work shows the fruitfulness of the concepts of "spiritual practice," "spiritual exercises" (P. Ado) for understanding not only philosophical thought, but also science. The problem of the influence of hermeticism on the genesis of modern science is analyzed in detail. Another focus of the study is the problem of finding an alternative to the "genealogical" reduction of cultural meanings, the ontological and methodological prerequisites of which are analyzed in Nietzsche's philosophy of life and Foucault's poststructuralism.