The opposition ‘logic/rhetoric’ represents a fundamental cultural antagonism. Surprising as it may seem, contemporary revival of the art of rhetoric has not been primarily promoted by scholars or professional users of rhetoric but developed itself through alternative, unusual paths, such as those of epistemology, logic and science. This is the case of the theory of knowledge (Polanyi) or of the improvements brought to informal logic by Perelman and Toulmin. Significant contributions to the history of science as well as to the Philosophy of Science have been made (by Thomas Kuhn among many others). At the core one always finds the same eternal and unresolved dilemma opposing truth to persuasion, i.e. to be true or to persuade/convince someone to believe that something is true. Persuasion and conviction are intimately connected with debate.