take
[ the set , the set , the set ]
; [ the set , the set , the set ] is triple
take
the set
; XTUPLE_0:def 5 ex x2, x3 being object st [ the set , the set , the set ] = [ the set ,x2,x3]
take
the set
; ex x3 being object st [ the set , the set , the set ] = [ the set , the set ,x3]
take
the set
; [ the set , the set , the set ] = [ the set , the set , the set ]
thus
[ the set , the set , the set ] = [ the set , the set , the set ]
; verum