The thesis of this essay is to show that there is a complex and deep ground in Hannah Arendt ́s political thinking. A ground that, thru Immanuel Kant ́s first and third critiques, is going back to the thinking of the ancient Greek ideas of insight, nous, a concept used especially by Aristotle, but also by Parmenides. My idea is that Arendt ́s attempt to establish her political thinking in the idea of common sense, or in Latin:sensus communis, needs a deeper understanding, thou the use and interpretation of common sense as a concept today is deeply under influence of a liberal ideological preunderstanding; meaning the (moral) things everyone knows without any special efforts. In my view there is no chance that Arendt joins, or supports that kind of shallow interpretation of the idea of common sense, thou that would make her political thinking as banal as she accuses most of the modern politics to be, which of course is very contradictive. In other words must her understanding of the concept of common sense, sensus communis, be founded on a much deeper level, a level which we can find in her essays if we look real hard, and read as open as a real reading must be based on. Her language and her recurring references to time, gives us the leads to where to dig; to where, and through which thinking, we can find her deeper ground, a ground that hopefully will make all her political thinking clearer.