In these pages I try to select within the semantics of fear that helps to organize the modern image of the political and legal order the specific element of panic, in the hypothesis that the latter constitutes a difference which is also an epistemic resource. Put a little shortly: if fear presents itself as a constitutive reference of the order, of its constitution as well as of its maintenance, panic seems instead charged with a contrary sign; it speaks to us of the dissolution of an aggregate given for presupposition and is in solidarity in defining its boundaries and conditions of possibility. The goal is to retrace some moments in the history of panic trying to argue that panic is a political passion, in the sense that it refers to what politics is made of, and at the same time is the expression of a limit 'passionate' of politics, in the sense that politically defines an internal limit. With respect to this objective, this contribution no longer claims that the characteristics of a basting in need of further development in reference not only to what is not included in it (and it is obviously a lot), but also to the knots that are indicated in a consciously provisional form. Furthermore, it limits itself to a historical periodization that is in some way preliminary, stopping at the threshold of the phase in which panic is a word of a disciplinary discourse, it is part of the object of a codified knowledge (psychology, sociology, science politics), even if it does not necessarily play a peaceful role in it.