Understanding Ken

Ken appeared on the English horizon in the 16th century as a term of measurement of the distance bounding the range of ordinary vision at sea—about 20 miles. British author John Lyly used that sense in 1580 when he wrote, "They are safely come within a ken of Dover." Other 16th-century writers used ken to mean "range of vision" ("Out of ken we were ere the Countesse came from the feast." — Thomas Nashe) or "sight" ("'Tis double death to drown in ken of shore." — Shakespeare). Today, however, ken rarely suggests literal sight. Rather, ken nowadays almost always implies a range of perception, understanding, or knowledge.