 The Buddhist thinker, Dignāga (c. 5th – 6th century ce), consolidates the insights into the canonical deductively valid syllogism of his predecessors, and in particular those of his teacher, Vasubandhu, as well as deepens them. He is, in fact, a pivotal figure in the history of Indian logic. This section is divided into two parts: the first devoted to Dignāga’s contributions to Indian logic, especially the canonical syllogism, the second part summarizing other contributions from his contemporaries and successors, both Buddhist and non-Buddhist.