We not only admit, but we assert, that in the physical world there are causes and effects. We insist that there is and can be no effect without an efficient cause. When anything happens in that world, we are satisfied that it was naturally and necessarily produced. The causes may be obscure, but we as implicitly believe in their existence as when we know positively what they are. In the physical world we have taken the ground that there is nothing miraculous--that everything is natural--and if we cannot explain it, we account for our inability to explain, by our own ignorance. Is it not possible, is it not probable, that what is true in the physical world is equally true in the realm of mind--in that strange world of passion and desire? Is it possible that thoughts or desires or passions are the children of chance, born of nothing? Can we conceive of nothing as a force, or as a cause? If, then, there is behind every thought and desire and passion an efficient cause, we can, in part at least, account for the actions of men. A certain man under certain conditions acts in a certain way. There are certain temptations that he, with his brain, with his experience, with his intelligence, with his surroundings cannot withstand. He is irresistibly led to do, or impelled to do, certain things; and there are other things that he can not do. If we change the conditions of this man, his actions will be changed. Develop his mind, give him new subjects of thought, and you change the man; and the man being Changed, it follows of necessity that his conduct will be different. In civilized countries the struggle for existence is severe--the competition far sharper than in savage lands. The consequence is that there are many failures. These failures lack, it may be, opportunity or brain or moral force or industry, or something without which, under the circumstances, success is impossible. Certain lines of conduct are called legal, and certain others criminal, and the men who fail in one line may be driven to the other. How do we know that it is possible for all people to be honest? Are we certain that all people can tell the truth? Is it possible for all men to be generous or candid or courageous?