The arguments it presents can not be answered by all the theologians in the world. The author is convinced that the universe is natural, that man is naturally produced, and that there is a necessary relation between character and brain. He sees, and clearly sees, that the theological explanation of phenomena is only a plausible absurdity, and, at best, as great a mystery as it tries to solve. I thank the man who breaks, or tries to break, the chains of custom, creed, and church, and gives in plain, courageous words, the product of his brain. It is almost impossible to investigate any subject without somewhere touching the religious prejudices of ourselves or others.
Most people judge of the truth of a proposition by the consequences upon some preconceived opinion.
Certain things they take as truths, and with this little standard in their minds, they measure all other theories. If the new facts do not agree with the standard, they are instantly thrown away, because it is much easier to dispose of the new facts than to reconstruct an entire philosophy. A few years ago, when men began to say that character could be determined by the form, quantity, and quality of the brain, the religious world rumbled to the conclusion that this fact might destroy what they were pleased to call the free moral agency of man. They admitted that all things in the physical world were links in the infinite chain of causes and effects, and that not one atom of the material universe could, by any possibility, be entirely exempt from the action of every other. In other words, they insisted that, while there were causes for all material phenomena, a something called the Will sat enthroned above all law, and dominated the phenomena of the intellectual world.