The summits Social_event were not meant to be linked Connect formally with wider international institutions ; and in fact , a mild rebellion Change_of_leadership against the stiff formality of other international meetings Communication was a part of the genesis of cooperation between France 's President Giscard d'Estaing and Germany 's Chancellor Helmut Schmidt as they conceived Creating the initial summit Social_event of the Group of Six ( G6 ) in 1975 .