theorem Th33: :: KNASTER:33

for L being complete Lattice
for f being monotone UnOp of L
for a, b being Element of L st a is_a_fixpoint_of f & b is_a_fixpoint_of f holds
ex O being Ordinal st
( card O c= card the carrier of L & (f,O) -. (a "/\" b) is_a_fixpoint_of f & (f,O) -. (a "/\" b) [= a & (f,O) -. (a "/\" b) [= b )