1. Vxvy (P(x,y) → Q(x)) 2. Vxy P(x,y) →\xQ(x) 2.1 Vxy P(x, y) 2.2 JyP (a, y) 2.3 ??? 2.4 Vy(P(a,y) → Q(a)) 2.5 P(a, b)→ Q(a) 2.6 Q(a) 2.7 VxQ(x) Data Subcomputation Assumption (UI) 2.1 (EI) 2.2 ??? (UI) 2.4 (→→E) 2.2 & 2.5 (UG) 2.6

What is the missing formula from line 2.3?

P(a,y)

P(a,b)

P(a,a)

∃x∃yP(x,y)


What is the missing rule from line 2.4?

(EI) 2.2

(→→I) 2.3

(UG) 2.5

(UI) 1.