From Helen Keller’s book, “Optimism”; published 1903

“I know what evil is. Once or twice I have wrestled with it, and for a time felt its chilling touch on my life; so I speak with knowledge when I say that evil is of no consequence, except as a sort of mental gymnastic. For the very reason that I have come in contact with it, I am more truly an optimist. I can say with conviction that the struggle which evil necessitates is one of the greatest blessings. It makes us strong, patient, helpful men and women. It lets us into the soul of things and teaches us that although the world is full of suffering, it is full also of the overcoming of it. My optimism, then, does not rest on the absence of evil, but on a glad belief in the preponderance of good and a willing effort always to cooperate with the good, that it may prevail. I try to increase the power God has given me to see the best in everything and every one, and make that Best a part of my life. The world is sown with good; but unless I turn my glad thoughts into practical living and till my own field, I cannot reap a kernel of the good.”

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“The test of all beliefs is their practical effect in life. If it be true that optimism compels the world forward, and pessimism retards it, then it is dangerous to propagate a pessimistic philosophy. One who believes that the pain in the world outweighs the joy, and expresses that unhappy conviction, only adds to the pain. … Life is a fair field, and the right will prosper if we stand by our guns.”

“Let pessimism once take hold of the mind, and life is all topsy-turvy, all vanity and vexation of spirit. … If I regarded my life from the point of view of the pessimist, I should be undone. I should seek in vain for the light that does not visit my eyes and the music that does not ring in my ears. I should beg night and day and never be satisfied. I should sit apart in awful solitude, a prey to fear and despair. But since I consider it a duty to myself and to others to be happy, I escape a misery worse than any physical deprivation.”