  I consider the problem of computing the mass of a charged, gravitating
particle in quantum field theory. It is shown how solving for the first
quantized propagator of a particle in the presence of its own potentials
reproduces the gauge and general coordinate invariant sum over an infinite
class of diagrams. The distinguishing feature of this class of diagrams is that
all closed loops contain part of the continuous matter line running from early
to late times. The next order term would have one closed loop external to the
continuous matter line, and so on. I argue that the gravitational potentials in
the 0-th order term may permit the formation of bound states, which would then
dominate the propagator. It is conceivable that this provides an tractable
technique for computing the masses of fundamental particles from first
principles. It is also conceivable that the expansion in external loops permits
gravity to regulate certain ultraviolet divergences.
