set X = the object ;
take
[ the object , the object , the object , the object , the object ]
; [ the object , the object , the object , the object , the object ] is quintuple
take
the object
; CLASSES5:def 2 ex x2, x3, x4, x5 being object st [ the object , the object , the object , the object , the object ] = [ the object ,x2,x3,x4,x5]
take
the object
; ex x3, x4, x5 being object st [ the object , the object , the object , the object , the object ] = [ the object , the object ,x3,x4,x5]
take
the object
; ex x4, x5 being object st [ the object , the object , the object , the object , the object ] = [ the object , the object , the object ,x4,x5]
take
the object
; ex x5 being object st [ the object , the object , the object , the object , the object ] = [ the object , the object , the object , the object ,x5]
take
the object
; [ the object , the object , the object , the object , the object ] = [ the object , the object , the object , the object , the object ]
thus
[ the object , the object , the object , the object , the object ] = [ the object , the object , the object , the object , the object ]
; verum