Determinism, Self-Causality, Mass

Free Will can be conceived as a Cause that is not the Effect of a prior Cause.  Accordingly, Determinism can be conceived as entailing the denial of the possibility of a Free Will.  However, that concept does not preclude the possibility of a vacillation between Causes, which is the variety of Determinism which Spinoza exemplifies.  For, in his system, behavior can be either self-caused or externally caused, neither of which is a case of Free Will.  This variability is grounded in the possibility of internal strengthening via the acquisition of Adequate Ideas, i. e. via empowering education.  In Newtonian terms, the variability is in the Mass of an object, i. e. in its capacity to resist external forces, and to effect external objects.  In his apparent allusion to Spinoza in order to reinforce his advocacy of Determinism, Einstein seems unaware of these nuances.