We present a universal particle equation where what we experience as mass is taken as resistance to changes in a particle’s motion through the temporal dimensions, which is measured by G, the universal constant of gravitation. To do this we introduce a normal force given by \( F_n = h/(c t_1^2) \) where is on the order of \( t_1 = 1 \) second, which is Lorentz invariant. The normal force, is exposed to the cross-sectional area of the particle A_i=\pi r_i^2. The result is the mass of the particle is given by \( m_i = \kappa_i \sqrt{\pi r_i^2 F_n/G} \), with experimental verification giving 1.00500 seconds (proton), 1.00478 seconds (neutron), and 0.99773 seconds (electron). The coupling constant, \kappa_i,, is predicted by a prediction for the radius of the proton, which is r_p=\phi h/(cm_p) with 1/\phi=\Phi where \Phi=(\sqrt{5}+1)/2 is the golden ratio, Thus we have a geometric mechanism for inertia, where we experience mass when we push on it, as resistance to diverting temporal motion into spacial dimensions.