If the Catholic Church had used infallibility in the way that Newman did, its influence could never have been accused of oppression. There need never have been any warfare between theology and science. Infallibility affords the Church an adroit way of continuing its spiritual existence while it permits free speculation in science and ethics to go on. Suppose the Church in its infallibility had not stuck to dogma. Suppose the reformers had been successful, and the Church had accepted early scientific truth. Suppose it had refused any longer to insist on correctness in theological belief but had insisted on correctness in scientific belief. Suppose the dogmas of the Resurrection had made way for the first crude imperfect generalizations in physics. Imagine the hideousness of a world where scientific theories had been declared infallible by an all-powerful Church! Our world’s safety lay exactly in the Church’s rejection of science. If the Church had accepted science, scientific progress would have been impossible. Progress was possible only by ignoring the Church. Knowledge about the world could only advance through accepting gratefully the freedom which the Church tacitly offered in all that fallible field of the technique of earthly living. What progress we have we owe not to any overcoming or converting of the Church but to a scrupulous ignoring of her. In punishing heresy the Church worked with a sound intuition. For a heretic is not a man who ignores the Church. He is one who tries to mix his theology and science. He could not be a heretic unless he were a victim of muddy thinking, and as a muddy thinker he is as much a nuisance to secular society as he is to the Church against which he rebels. He is the officious citizen who tries to break into the storage-vault with the benevolent intention of showing that the jewels are paste. But all he usually accomplishes is to set the whole town by the ears. The constructive daily life of the citizens is interrupted in a flood of idle gossip. It is as much to the interest of the intelligent authorities, who have important communal projects on hand, to suppress him as it is to the interest of the owner of the jewels. Heresy is fundamentally the error of trying to reconcile new knowledge with old dogma. The would-be heretic could far more wisely ignore theology altogether and pursue his realistic knowledge in the aloofness which it requires. If there is still any theological taint in him, he should not dabble in science at all. If there is none, the Church will scarcely feel itself threatened and he will not appear as a heretic. On the pestiferousness of the heretic both the Church and the most modern realist can agree. Let theology deal with its world of dogma. Let science deal with its world of analysable and measurable fact. Let them never touch hands or recognize even each other’s existence.