Former Illinois Supreme Court Chief Justice Benjamin K. Miller, who wrote 500 opinions on the state high court and spent his retirement sailing the world, died Sunday at 87.Miller was elected to the Supreme Court in 1984, won retention in 1990 and served as chief justice from 1991 to 1993.“Justice Miller will forever be known as a giant of the Illinois judicial and legal communities,” Chief Justice Mary Jane Theis said in the court’s announcement. “He provided steady leadership and moved the courts …