Higgs invented a mechanism to endow quarks and leptons an W- and Z-particles with mass. If a particle is massless though then how can it be slowed down by interacting with another particle? Maybe the particle gets an effective mass (like a photon traveling through a medium though its velocity can't change contrary to that of quarks and leptons) but the mass of the particle itself will not change. Its motion will at the most be retarded and thus make it seem the particle has a speed smaller than the speed of light and thus (effective) mass.
What was Higgs' attitude towrds his own mechanism? Did he think in terms of an effective mass?
