[Cannabis, hemp and hashish: always returning].

Cannabis has a long story, the story of an endless return through ages and countries, all over the world. There is no mention of an "hedonist" use of cannabis in Ancient Greek or Roman sources but cannabism is largely attested in Orient as early as in the Middle Ages, even if many tales about Haschishins and Crusaders remain highly controversial. The "come back" of cannabism can be traced back in Europe at the end of XVIIIth century after the Egyptian campaigns of Bonaparte. Thus was launched an increasing vogue of orientalism, soonly after followed by the emergence of cannabism in Paris or London and, half a century later, the United States. After a brief armistice, cannabis rises up again with force at the end of XXth century, all over the world. In our times cannabis remains in the centre of all discussions about hallucinogen substances and many ethical, moral or medical questions are still unanswered. Our final comments will go to the everlasting "come back" of cannabism: search of exotism, attempt to escape from reality or as suggested by recent physiologic studies, close inter-relations between sensorial paths and the upper brainstem centers.