Legal realism was primarily a reaction to the legal formalism of the late 19th century and early 20th century, and was the dominant approach for much of the early 20th century. It succeeded in its negative aspiration of casting doubt upon formalist assumptions that judges always did what they said so that it is often said that 'we are all realists now.' However, realism failed in its positive aspiration of discovering a better way of predicting how judges would behave than relying on the reasons given by judges.