Substitution Let e be s 1.0(A)=St. tn A if A is atomic. (the result of simultaneously substituting ti for wi for Kn at all) 2.6(~B)=~(B) 3. 0(BVC)=0(B)VAC) 4.6xB)= VcA(B ∈{x1 t1,…,t;-1,t b if a Logic in Computer Science - p 9/23Substitution Let θ be Sx1,···,xn t1,···,tn . 1. θ(A) = Sx1,···,xn t1,···,tn A if A is atomic. (the result of simultaneously substituting ti for xi for 1 ≤ i ≤ n at all) 2. θ(∼ B) =∼ θ(B) 3. θ(B ∨ C) = θ(B) ∨ θ(C) 4. θ(∀xB) =  ∀xθ(B) if y 6∈ {x1, · · · , xn} ∀xSx1,···,xi−1,xi+1,···,xn t1,···,ti−1,ti+1,···,tn B if x = xi Logic in Computer Science – p.9/23