Probably his keen sense of humor would have preserved him from this not uncommon error. It is said that the secret of humor is the quick perception of incongruous relations. This would seem to have been the secret of Mr. Beecher's humor, for he had in an eminent degree what the phrenologists call the faculty of comparison. This was seen in his arguments, which were more often analogical than logical; seen not less in that his humor was not employed with deliberate intent to relieve a too serious discourse, but was itself the very product of his seriousness. He was humorous, but rarely witty, as, for the same reason, he was imaginative but not fanciful. For both his imagination and his humor were the servants of his moral purpose; and as he did not employ the one merely as a pleasing ornament, so he never went out of his way to introduce a joke or a funny story to make a laugh. Speaking broadly, Mr. Beecher's style as an orator passed through three epochs. In the first, best illustrated by his 'Sermons to Young Men,' preached in Indianapolis, his imagination is the predominant faculty. Those sermons will remain in the history of homiletical literature as remarkable of their kind, but not as a pulpit classic for all times; for the critic will truly say that the imagination is too exuberant, the dramatic element sometimes becoming melodramatic, and the style lacking in simplicity. In the second epoch, best illustrated by the Harper and Brothers edition of his selected sermons, preached in the earlier and middle portion of his Brooklyn ministry, the imagination is still pervasive, but no longer predominant. The dramatic fire still burns, but with a steadier heat. Imagination, dramatic instinct, personal sympathy, evangelical passion, and a growing philosophic thought-structure, combine to make the sermons of this epoch the best illustration of his power as a popular preacher. In each sermon he holds up a truth like his favorite opal, turning it from side to side and flashing its opalescent light upon his congregation, but so as always to show the secret fire at the heart of it. In the third epoch, best illustrated by his sermons on Evolution and Theology, the philosophic quality of his mind predominates; his imagination is subservient to and the instrument of clear statement, his dramatic quality shows itself chiefly in his realization of mental conditions foreign to his own, and his style, though still rich in color and warm with feeling, is mastered, trained, and directed by his intellectual purpose. In the first epoch he is the painter, in the second the preacher, in the third the teacher.