We live on an island surrounded by a sea of ignorance. As our island of knowledge grows, so does the shore of our ignorance."- John Archibald Wheeler

You can swim all day in the Sea of Knowledge and still come out completely dry. Most people do."
-Norman Juster

so we r learning day by day.We cant complete our knowledge even by using our entire life.Its vast and endless.Learning process continues till our death.Then also we may feel ignorant.It tells the thruth that "none is perfect".he is always ignorant.