The routine answer to this riddle has always been, "to get to the other side". This riddle appeared in an edition of a New York monthly magazine named the Knickerbocker in 1847. Since then, people have supplied different answers, such as "it was too far to walk around" or "to find the rooster". Einstein has creatively invented another reason. Apparently the chicken crosses the road to see a squirrel! Makes perfect sense!