| a0 ∈ st, (∀ a. a ∈ st → a ∈ st0 ∧ st[a] = st0[a]) ∧ ¬ a ∈ st ∨ a ∈ st ∧ st[a] = d ∧ (∀ a1. a1 ∈ st -- a → a1 ∈ st0 -- a ∧ st[a1] = st0[a1]) ⊦ a0 = a, a0 ∈ st0 ∧ st[a0] = st0[a0] |
a0 ∈ st, ∀ a. a ∈ st → a ∈ st0 ∧ st[a] = st0[a] ⊦ a0 = a, a ∈ st, a0 ∈ st0 ∧ st[a0] = st0[a0]
st[a] = d, a0 ∈ st, a ∈ st, ∀ a1. a1 ∈ st -- a → a1 ∈ st0 -- a ∧ st[a1] = st0[a1] ⊦ a0 = a, a0 ∈ st0 ∧ st[a0] = st0[a0]