Definition:Set/Historical Note

Historical Note on Set
The concept of a set first appears in 's posthumous ($1851$) work (The Paradoxes of the Infinite).

The first investigation into the concept in any depth was made by in his two papers called Beiträge zur Begründung der transfiniten Mengenlehre ($1895$ and $1897$).

It was who, in $1874$, defined a set thus:
 * By a set $M$ we understand any collection into a whole of definite and separate objects $m$ of our intuition or our thought.

Hence the definition of a set as:
 * a Many that allows itself to be thought of as a One.
 * --, and , Gesammelte Abhandlungen (Berlin: Springer-Verlag, $1932$)

This definition was directly inspired by a problem raised by in his paper  of $1854$, on the subject of Fourier series.