A man who thoroughly knows the world must be capable of understanding all phases of life,--not only those of his own country, class, profession, or sect. It is the humanity in all its phases that he loves and understands,--not the phase itself; and therefore nothing that is human can be so remote as to be unintelligible to his mind or without the power of appeal to his heart. Iago could never understand honesty or generosity. Don Juan could never understand chastity. On the other hand it is possible for an honest man to understand Iago, and for a clean man to understand Don Juan. Although in neither case will the man who understands sympathize with the sin, in both cases the understanding will be clear and comprehensive. A child cannot understand either Iago or Don Juan, neither can a childish man; but a truly _childlike_ man can understand all phases of temptation and sin, and estimate them justly. There is an innocence of ignorance, and there is an innocence of wisdom. The innocence of ignorance is involuntary. It is innocence because it cannot be anything else. A little child is in the innocence of ignorance, and it is from that protective innocence that we feel the fresh, happy atmosphere of childhood. The innocence of wisdom is possible only to those who have known temptation and, through overcoming it, have learned to recognize all sin for what it really is,--the filth and disease of the soul, and to avoid it as such. The fresh life that springs from such struggle and conquest of selfish tendencies brings with it a vigor of innocence which has a quality of life akin to that of a healthy child, with the added power and insight of a man's maturity. Whatever form or phase of temptation his fellow men may be in, such a man, from his own experience, has found the means of understanding them. He has found the means of understanding his neighbor, whether the neighbor is immersed in self-indulgence, is struggling desperately to gain his freedom, or is well along upon the upward path. A man who can only understand certain special phases of human nature is narrow and provincial, however he may assume the air of a man of the world; and the false assumption of a broad understanding renders him practically still more narrow and provincial, for it stands in the way of his learning from those who have it in their power to instruct him. But the true man of the world, whose breadth of vision and penetration of insight are the result of a working familiarity with universal principles in practical life, detests sin without condemning the sinner, and is not befooled by the shallow pretensions of the provincial Pharisee.