| # st0 ≤ # st1, st1[a, d] ⊆ st0, ∀ st. ¬ # st < # st1 ∨ ¬ st1 ⊆ st ⊦ st1[a, d] = ∅, a ∈ st1 |
⊦ st[a, d] ⊆ st0 ↔ st -- a ⊆ st0 -- a ∧ a ∈ st0 ∧ st0[a] = d
st0[a] = d, a ∈ st0, # st0 ≤ # st1, st1 -- a ⊆ st0 -- a, ∀ st. ¬ # st < # st1 ∨ ¬ st1 ⊆ st ⊦ st1[a, d] = ∅, a ∈ st1
Used terms: st0, d, a, st1