  The chirality is the key for our world. In this scheme, I present a solution
of the long standing gauge hierarchy problem with a hidden sector SU(5)$'$ with
representations $\overline{\bf 10}\oplus \overline{\bf 5}\oplus 2\cdot{\bf 5}$.
Sideway remarks are on {\it NATURAL HILLTOP} inflation and a bound on the QCD
angle $\bar\theta$.
