This article deals with the notion of sovereignty as found in the second volume of Derrida's seminar La bte et le souverain. in this seminar, Derrida shows that the foundations of political sovereignty are theological, and analyses the way in which, by reading the Bible, Robinson gradually considers himself the absolute sovereign of his island by the grace of God. This leads him, however, to absolute solitude (or rather sovereignty comes from solitude), the solitude of his isolation on the island. This solitude turns out to be a constant motif in the foundation of Modernity, be it with Descartes (with the cogito as a Robinsonian hyperbole) or with Rousseau, and is not far from a certain way of reading, or rather from a renunciation of reading. Heidegger shares such solitude of the sovereign in his conception of Dasein or this isolating sovereignty, but yet opens another possibility (or we open it by reading him somewhere else or otherwise): Derrida analyses at length the uses of the Heideggerian term Walten as the source of the ontological difference that alludes to another form of sovereignty: sovereignty of nothing or sovereign neutrality.