The article is devoted to the substantiation of the statement that the Buddhist
vyākaraṇa is the method of rational ‘forecast’ and at the same time the ‘fore-knowledge’
(from Greek prognosis) itself. The proofs that the conventional meaning ‘prophecy’ is
invalid are given. The reasons of the opinion that vyākaraṇa is the ‘prognosis’ are based
of Buddhist canonical and post-canonical texts. Vyākaraṇa as the dialectical method of
the Buddhist philosophy allows to model the scheme of the good conduct that leads to
the obtaining of the final goal of the Buddhist spiritual practice — the attainment of
nirvāṇa.