  Following the Witten-Nester formalism, we present a useful prescription using
Weyl spinors towards the positivity of mass. As a generalization of
arXiv:1310.1663, we show that some "positivity conditions" must be imposed upon
the gauge connections appearing in the supercovariant derivative acting on
spinors. A complete classification of the connection fulfilling the positivity
conditions is given. It turns out that these positivity conditions are indeed
satisfied for a number of extended supergravity theories. It is shown that the
positivity property holds for the Einstein-complex scalar system, provided that
the target space is Hodge-Kahler and the potential is expressed in terms of the
superpotential. In the Einstein-Maxwell-dilaton theory with a dilaton
potential, the dilaton coupling function and the superpotential are fixed by
the positive mass property. We also explore the $N=8$ gauged supergravity and
demonstrate that the positivity of the mass holds independently of the gaugings
and the deformation parameters.
