and white is in control of the centre. After 4...dxc6, the obvious 5.Nxe5? is weak, since 5...Qd4! 6.Nf3 Qxe4+ 7.Qe2 Qxe2+ leaves White with no compensation   for Black's bishop pair. There are two principal lines after 4.Bxc6 dxc6. In the late 19th century and early 20th century, Lasker had great