While tolerance is acclaimed almost unanimously as an indispensable value in pluralistic and democratic societies, the meaning of this virtue is in fact far from obvious. There are good reasons to believe that the inflationary expectations addressed to it tend to cover up its specific difficulty. The A. therefore offers a conceptual analysis of the conditions of tolerance, placing particular emphasis on the conflict of reasons internal to the tolerating person, and pointing to the reflective structure of practical reason. In this formal characterization, tolerance appears as a kind of permission grounded in the principle of exclusion of certain reasons for acting. If indeed tolerance presupposes such a complex balance of reasons, its moral ...