Euler

Topology starts here -- Konigsberg bridges.

This is what Leibniz called “geometry of position” but what exactly did he mean? We know what Euler meant: “this branch is concerned only with the determination of position and its properties; it does not involve distances, nor calculations made with them... “a problem was recently mentioned, which seemed geometrical but was so constructed that it did not require the measurement of distances, nor did calculation help at all, I had no doubt that it was concerned with the geometry of position.”