“Heresy is the eternal dawn, the morning star, the glittering herald of the day. Heresy is the last and best thought. It is the perpetual New World, the unknown sea, toward which the brave all sail. It is the eternal horizon of progress.Heresy extends the hospitalities of the brain to a new thought.Heresy is a cradle; orthodoxy, a coffin.”

“Progress is born of doubt and inquiry. The Church never doubts, never inquires. To doubt is heresy, to inquire is to admit that you do not know—the Church does neither.”

“The glory of science is, that it is freeing the soul -- breaking the mental manacles -- getting the brain out of bondage -- giving courage to thought -- filling the world with mercy, justice, and joy.”

“Like the most of you, I was raised among people who knew - who were certain. They did not reason or investigate. They had no doubts. They knew that they had the truth. In their creed there was no guess — no perhaps. They had a revelation from God. They knew the beginning of things. They knew that God commenced to create one Monday morning, four thousand and four years before Christ. They knew that in the eternity — back of that morning, he had done nothing. They knew that it took him six days to make the earth — all plants, all animals, all life, and all the globes that wheel in space. They knew exactly what he did each day and when he rested. They knew the origin, the cause of evil, of all crime, of all disease and death.At the same time they knew that God created man in his own image and was perfectly satisfied with his work... They knew all about the Flood -- knew that God, with the exception of eight, drowned all his children -- the old and young -- the bowed patriarch and the dimpled babe -- the young man and the merry maiden -- the loving mother and the laughing child -- because his mercy endureth forever. They knew too, that he drowned the beasts and birds -- everything that walked or crawled or flew -- because his loving kindness is over all his works. They knew that God, for the purpose of civilizing his children, had devoured some with earthquakes, destroyed some with storms of fire, killed some with his lightnings, millions with famine, with pestilence, and sacrificed countless thousands upon the fields of war. They knew that it was necessary to believe these things and to love God. They knew that there could be no salvation except by faith, and through the atoning blood of Jesus Christ.Then I asked myself the question: Is there a supernatural power -- an arbitrary mind -- an enthroned God -- a supreme will that sways the tides and currents of the world -- to which all causes bow?I do not deny. I do not know - but I do not believe. I believe that the natural is supreme - that from the infinite chain no link can be lost or broken — that there is no supernatural power that can answer prayer - no power that worship can persuade or change — no power that cares for man.Is there a God?I do not know.Is man immortal?I do not know.One thing I do know, and that is, that neither hope, nor fear, belief, nor denial, can change the fact. It is as it is, and it will be as it must be.We can be as honest as we are ignorant. If we are, when asked what is beyond the horizon of the known, we must say that we do not know. We can tell the truth, and we can enjoy the blessed freedom that the brave have won. We can destroy the monsters of superstition, the hissing snakes of ignorance and fear. We can drive from our minds the frightful things that tear and wound with beak and fang. We can civilize our fellow-men. We can fill our lives with generous deeds, with loving words, with art and song, and all the ecstasies of love. We can flood our years with sunshine — with the divine climate of kindness, and we can drain to the last drop the golden cup of joy.”

“The real bible is not the work of inspired men, nor prophets, nor apostles, nor evangelists, nor of Christs. Every man who finds a fact, adds, as it were, a word to this great book. It is not attested by prophecy, by miracles or signs. It makes no appeal to faith, to ignorance, to credulity or fear. It has no punishment for unbelief, and no reward for hypocrisy. It appeals to man in the name of demonstration. It has nothing to conceal. It has no fear of being read, of being contradicted, of being investigated and understood. It does not pretend to be holy, or sacred; it simply claims to be true. It challenges the scrutiny of all, and implores every reader to verify every line for himself. It is incapable of being blasphemed. This book appeals to all the surroundings of man. Each thing that exists testifies of its perfection. The earth, with its forests and plains, its rocks and seas; with its every wave and cloud; with its every leaf and bud and flower, confirms its every word, and the solemn stars, shining in the infinite abysses, are the eternal witnesses of its truth.”

“If abuses are destroyed, man must destroy them. If slaves are freed, man must free them. If new truths are discovered, man must discover them. If the naked are clothed; if the hungry are fed; if justice is done; if labor is rewarded; if superstition is driven from the mind; if the defenseless are protected and if the right finally triumphs, all must be the work of man. The grand victories of the future must be won by man, and by man alone.”

“I will not attack your doctrines nor your creeds if they accord liberty to me. If they hold thought to be dangerous - if they aver that doubt is a crime, then I attack them one and all, because they enslave the minds of men.I attack the monsters, the phantoms of imagination that have ruled the world. I attack slavery. I ask for room -- room for the human mind.”