π. π ππ’π΄ ππ²π«π‘ππͺπ’π«π±ππ© ππ¬π±π¦π¬π«: βπ¦π’πͺππ«π«’π° πππ«π¦π£π¬π©π‘π°
ππ₯πΆπ«π’π°π°, a natural consequence of his earlier sheltered life [as a child], ... never left him completely ... and frequently moved him to abandoned himself to soltiude and to his mental universe, in which he unfolded [his thoughts with] the greatest boldness and lack of prejudices.¹ βπ« mathematics, the art of posing questions is more consequential then that of solving them.² βπ« this chapter we trace back the first influential appearance of a set-theoretical viewpoint to the work of Riemann. Of course, by speaking of "a set-theoretical viewpoint" I do not mean to suggest that Riemann reached technical results that we would classify today as belonging to set theory ... only that he introduced set language substantially in this treatment of mathematical theories and regarded set as a foundation of mathematics. This comes out in a public lecture given in 1854, on the occasion of his Habilitation as a professor at GΓΆttingen. When he proposed a general notio...