The nineteenth century saw the paradoxes and obscurities of
eighteenth-century calculus gradually replaced by the exact theorems and
statements of rigorous analysis. It became clear that all analysis could
be deduced from the properties of the real numbers. But what are the
real numbers and why do they have the properties we claim they do? In
this charming and influential book, Richard Dedekind (1831 1916),
Professor at the Technische Hochschule in Braunschweig, showed how to
resolve this problem starting from elementary ideas. His method of
constructing the reals from the rationals (the Dedekind cut) remains
central to this day and was generalised by Conway in his construction of
the 'surreal numbers'. This reissue of Dedekind's 1888 classic is of the
'second, unaltered' 1893 edition.