Conscience is our magnetic compass; reason our chart.

Later Cook switched to the Free Trade Party and was a minister in the cabinet of Premier George Reid from 1894 to 1899. Following a split in the Labor party in 1916 Cook joined William Morris Hughes' Nationalist Party of Australia and following the Nationalist victory in the 1917 election served as Minister for the Navy then Treasurer under Hughes. During Australia's first federal election in 1901 Cook was elected unopposed to the federal seat of Parramatta and served as the deputy to Reid then Alfred Deakin following the creation of the Commonwealth Liberal Party from Cook's and Deakin's parties.