If there is a counterfeit Mona Lisa, there is the real one. If there are counterfeit US dollars, there are real US dollars. We shall generalize this and call it the Counterfeit Dependence principle, i.e. all counterfeits imply the existence of some reality upon which they are based. We can apply this principle to the question of whether there is a real Mass, i.e. a real liturgy in which Christs sacrifice is offered to the Father.LetCx x is counterfeitMx x is a MassRx x is realA(x,P) x appears to be a P-like thingBxy x is based upon y1. (x)(P){[Cx A(x,P)] (y)[(Ry Py) Bxy]} (Counterfeit Dependence premise)2. (x)(Cx A(x,M) (premise)3. C A(,M) (2 EI)4. (P){[C A(,P)] (y)[(Ry Py) By]} (1 UI)5. [C A(,M)] (y)[(Ry My) By] (4 UI)6. (y)[(Ry My) By](2,5 MP)7. (R M) B (6 EI)8. (R M) (7 Simp)9. (x)(Rx Mx) (8 EG) If there is a counterfeit Mass, there is a real Mass. Since there are such counterfeits, there is a real Mass.QEDSee also: https://vexingquestions.wordpress.com/2014/08/24/the-sacred-and-the-sacrilegious-the-real-presence-and-a-black-mass/