How many knuckleball pitchers are in baseball today?

The identity of the first pitcher to throw a knuckleball is uncertain, but it appears to have been developed in the early 20th century. Lew "Hicks" Moren of the Philadelphia Phillies was credited as its inventor by the New York Press in 1908. However, Eddie Cicotte apparently also came up with the pitch while at Indianapolis in 1906, and brought it to the major leagues with him two years later. Since Cicotte had a much more successful career (and also gained later notoriety as one of the Black Sox), his name is the one most often associated with the invention of the pitch today.