| 1 | 11. L:Sequent List.
s L.( (s) = 0)
& ( s L.|= s  |= < hyp,x1.(M @ N) > )
& ( a:Assignment. s L.a | s  a | < hyp,x1.(M @ N) > ) 12. L:Sequent List.
s L.( (s) = 0)
& ( s L.|= s  |= < hyp,x2.(M @ N) > )
& ( a:Assignment. s L.a | s  a | < hyp,x2.(M @ N) > ) L:Sequent List.
s L.( (s) = 0)
& ( s L.|= s  |= < hyp,M @ (x1  x2.N) > )
& ( a:Assignment. s L.a | s  a | < hyp,M @ (x1  x2.N) > ) |