Tweet Ignorance, the root and stem of all evil. Quote by Plato. You May Also Like...There is only one good, knowledge, and one evil, ignorance.Think good, and good follows. Think evil, and evil follows. You are what you think all day long.Thinking is the talking of the soul with itself.The greatest enemy of knowledge is not ignorance, it is the illusion of knowledge.There are two things a person should never be angry at, what they can help, and what they cannot.We are twice armed if we fight with faith.Good actions give strength to ourselves and inspire good actions in others.For a man to conquer himself is the first and noblest of all victories.Never discourage anyone who continually makes progress, no matter how slow.