This article deals with the role of negation as a language and cognitive operation. Such a topic is treated here within the framework of the argumentative strategies which consist in making certain cognitive landmarks of the discourse ‘flip over’ with the intent of imposing the necessity to choose between two types of ‘notions’, aiming at the transformation of this choice into an ‘implication’. The reference here to the Aristotelian logic of Prior Analytics appears to be more efficient than any other (...) contemporary logic and the author intends to give account of the role of negation as ‘contrary’ coming into play on an operational and cognitive basis in all the argumentative strategies which ‘oscillate’ reciprocally from universal to particular. (shrink)