theorem :: YELLOW_0:65
for L being non empty transitive RelStr
for S being non empty full SubRelStr of L
for x, y being Element of S st ex_inf_of {x,y},L & "/\" ({x,y},L) in the carrier of S holds
( ex_inf_of {x,y},S & "/\" ({x,y},S) = "/\" ({x,y},L) ) by Th63;