"Evil is nonexistent; it is the absence of good."

... "Man must walk in many paths and be subjected to various processes in his evolution upward. Physically he is not born in full stature but passes through consecutive stages of fetus, infant, childhood, youth, maturity and old age. Suppose he had the power to remain young throughout his life. He then would not understand the meaning of old age and could not believe it existed. If he could not realize the condition of old age, he would not know that he was young. He would not know the difference between young and old without experiencing the old. Unless you have passed through the state of infancy, how would you know this was an infant beside you? If there were no wrong, how would you recognize the right? If it were not for sin, how would you appreciate virtue? If evil deeds were unknown, how could you commend good actions? If sickness did not exist, how would you understand health? Evil is nonexistent; it is the absence of good. Sickness is the loss of health; poverty, the lack of riches. When wealth disappears, you are poor; you look within the treasure box but find nothing there. Without  knowledge there is ignorance; therefore, ignorance is simply the lack of knowledge. Death is the absence of life. Therefore, on the one hand, we have existence; on the other, nonexistence, negation or absence of existence.

Briefly, the journey of the soul is necessary. The pathway of life is the road which leads to divine knowledge and attainment. Without training and guidance the soul could never progress beyond the conditions of its lower nature, which is ignorant and defective."

`Abdu'l-Bahá, The Promulgation of Universal Peace. pp. 295-296

29 August 1912 
Talk at Home of Madame Morey 
34 Hillside Avenue, 
Malden, Massachusetts