3-sphere two 3-balls. This construction is analogous to a construction of a 2-sphere, performed by gluing the boundaries of a pair of disks. A disk is a 2-ball, and the boundary of a disk is a circle (a 1-sphere). Let a pair of disks be of the same diameter. Superpose them and glue corresponding points on their boundaries. Again one may think of the third dimension as temperature. Likewise, we may inflate the 2-sphere, moving the pair of disks to become the northern and southern hemispheres. After removing a single point from the 2-sphere, what remains is homeomorphic to the Euclidean
Private sphere of experiential knowledge and the world of the body – as against the (traditional) male preserves of public speech and theory. All the while, the public sphere of work, business, politics and ideas were increasingly opened up to female participation. Martin Heidegger argued that it is only in the private sphere that one can be one's authentic self, as opposed to the impersonal and identikit They of the public realm. Richard Sennett however opposed what he saw as the Romantic idealisation of the private realm of intimate relations, as opposed to the public sphere of action at a distance. Deleuze