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 rushed 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. They insisted that, if the motions of the spirit--the thoughts, dreams, and conclusions of the brain, were as necessarily produced as stones and stars, virtue became necessity, and morality the result of forces capable of mathematical calculation. 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. They insisted that man was free; that he controlled his brain; that he was responsible for thought as well as action; that the intellectual world of each man was a universe in which his will was king. They were afraid that phrenology might, in some way, interfere with the scheme of salvation, or prevent the eternal torment of some erring soul.
It is insisted that man is free, and is responsible, because he knows right from wrong. But the compass does not navigate the ship; neither does it, in any way, of itself, determine the direction that is taken. When winds and waves are too powerful, the compass is of no importance. The pilot may read it correctly, and may know the direction the ship ought to take, but the compass is not a force. So men, blown by the tempests of passion, may have the intellectual conviction that they should go another way; but, of what use, of what force, is the conviction?