This study focuses on two outstanding psychiatrists: the Frenchman Valentin Magnan (1835-1916) and the Russian Sergey Korsakov (1854-1900). Their international renown is primarily associated with their investigations into health consequences of alcohol consumption; they were pioneers in this field, and happened to know each other well. The similarities and differences are shown in social and scientific approaches adopted by these two scientists. In his work, Magnan focused mainly on absinthe and epilepsy; he considered alcoholism to be a hereditary mental disorder. Korsakov, after a period of work in Paris under Magnan's guidance, represented a more modern generation and was advancing fundamental ideas on the nature of psychoses and merging clinical features, somatic, psychological, and social factors. Although Magnan has practically disappeared from the current literature on alcoholism, Korsakov is still clearly present today.