  In this work, we seek a cosmological mechanism that may define the sign of
the effective gravitational coupling constant, {\em G}. To this end, we
consider general scalar-tensor gravity theories as they provide the field
theory natural framework for the variation of the gravitational coupling. We
find that models with a quadratic potential naturally stabilize the value of
{\em G} into the positive branch of the evolution and further, that de Sitter
inflation and a relaxation to General Relativity is easily attained.
