The retort - one of the most-difficult artforms to master. A brilliant comeback requires perfect timing, unrivalled wit and adequate context - and it must at least match, if not preferably out do, the original comment made. Comedians are naturally expected to be quick-witted and able to think-up a rapid yet amusing riposte, but any profession that involves debating and arguing - for example politics - also requires a certain retaliatory skill. Although shouting "BURN!", "OWNED!" or "CLAMPED!" when someone is put down by a rapid and brilliant retort may seem like a 21st-Century phenomenon, the skill of offering up a witty and amusing comeback has been around since the beginning of time. There are those from history who are renowned for their quick responses - including Sir Winston Churchill, who loved nothing better than to get the final word, and American comedian WC Fields - and then there are those who surprised from time to time by offering up the sole gem of a comeback here and there. Other names who appear on this list are Leo Tolstoy, James Joyce, Albert Einstein, John Wilkes - and even a 5th-Century BC Spartan warrior king named Pausanias. So, sit back and enjoy the 12 most-impressive retorts in history - because there are some absolute gems...