let X be set ; :: thesis: for A being Subset-Family of X holds TopStruct(# X,(UniCl (FinMeetCl A)) #) is TopSpace-like
let A be Subset-Family of X; :: thesis: TopStruct(# X,(UniCl (FinMeetCl A)) #) is TopSpace-like
per cases ( X = {} or X <> {} ) ;
suppose A1: X = {} ; :: thesis: TopStruct(# X,(UniCl (FinMeetCl A)) #) is TopSpace-like
set T = TopStruct(# X,(UniCl (FinMeetCl A)) #);
A2: the carrier of TopStruct(# X,(UniCl (FinMeetCl A)) #) in FinMeetCl A by CANTOR_1:8;
FinMeetCl A c= UniCl (FinMeetCl A) by CANTOR_1:1;
hence the carrier of TopStruct(# X,(UniCl (FinMeetCl A)) #) in the topology of TopStruct(# X,(UniCl (FinMeetCl A)) #) by A2; :: according to PRE_TOPC:def 1 :: thesis: ( ( for b1 being Element of bool (bool the carrier of TopStruct(# X,(UniCl (FinMeetCl A)) #)) holds
( not b1 c= the topology of TopStruct(# X,(UniCl (FinMeetCl A)) #) or union b1 in the topology of TopStruct(# X,(UniCl (FinMeetCl A)) #) ) ) & ( for b1, b2 being Element of bool the carrier of TopStruct(# X,(UniCl (FinMeetCl A)) #) holds
( not b1 in the topology of TopStruct(# X,(UniCl (FinMeetCl A)) #) or not b2 in the topology of TopStruct(# X,(UniCl (FinMeetCl A)) #) or b1 /\ b2 in the topology of TopStruct(# X,(UniCl (FinMeetCl A)) #) ) ) )

hence for a being Subset-Family of TopStruct(# X,(UniCl (FinMeetCl A)) #) st a c= the topology of TopStruct(# X,(UniCl (FinMeetCl A)) #) holds
union a in the topology of TopStruct(# X,(UniCl (FinMeetCl A)) #) by A1; :: thesis: for b1, b2 being Element of bool the carrier of TopStruct(# X,(UniCl (FinMeetCl A)) #) holds
( not b1 in the topology of TopStruct(# X,(UniCl (FinMeetCl A)) #) or not b2 in the topology of TopStruct(# X,(UniCl (FinMeetCl A)) #) or b1 /\ b2 in the topology of TopStruct(# X,(UniCl (FinMeetCl A)) #) )

thus for a, b being Subset of TopStruct(# X,(UniCl (FinMeetCl A)) #) st a in the topology of TopStruct(# X,(UniCl (FinMeetCl A)) #) & b in the topology of TopStruct(# X,(UniCl (FinMeetCl A)) #) holds
a /\ b in the topology of TopStruct(# X,(UniCl (FinMeetCl A)) #) by A1; :: thesis: verum
end;
suppose X <> {} ; :: thesis: TopStruct(# X,(UniCl (FinMeetCl A)) #) is TopSpace-like
end;
end;