Mr. Lincoln believed that: "He who knows only his own side of a case knows little of that." The first illustration of his peculiar mental operations which led him always to study the opposite side of every disputed question more exhaustively than his own, was on his first appearance before the Supreme Court of Illinois when he actually opened his argument by telling the court that after diligent search he had not found a single decision in favor of his case but several against it, which he then cited, and submitted his case. This may have been what Mr. Lincoln alluded to when he told Thurlow Weed that the people used to say, without disturbing his self-respect, that he was not lawyer enough to hurt him. The most important case Mr. Lincoln ever argued before the Supreme Court was the celebrated case of the Illinois Central Railroad Company vs. McLean County. The case was argued twice before this tribunal; one brief of which is among the forty pages of legal manuscript written by Mr. Lincoln in the writer's possession. While its four pages may have more historic value than a will case argued in the Circuit Court of Sangamon County, still the latter is chosen to illustrate the period of Mr. Lincoln's mature practice and to show his analytical methods, his original reasoning, and his keen sense of justice. The case is one wherein land has been left to three sons and a grandson and the personal estate to be divided among three daughters after the death of the widow. Mr. Lincoln is employed to defend the will against the three daughters and their husbands. The brief consists of fifteen pages of legal cap paper only four of which are here given. It is said that he wrote few papers, less perhaps than any other man at the bar; therefore this memorandum in his own hand is also valuable as an example of the notes he so rarely made. [Illustration: Correll & others } vs } Will Case-- M. Daniel & others } 1 General remarks on the law of Wills-- 2. Answer the particular points and objections made by the other side--See notes taken while they were speaking-- 3. Read from the authorities and settle on a +definition+ of "Sound mind and memory"-- 4 Show that in this case, the Testator had such "+Sound mind and memory+" at the time of making the Will-- 1 By his asking D^r Randall to write his Will. 2. His reply to M^{rs} Herron*, when she saw* he was too sick & weak to make Wills. 3. His saying his Will was already made, and getting roll of blank paper-- 4 His getting the package of title papers-- 5 His making first provision for his wife; and charge upon Sutcliff for her and his sisters-- 6 His deciding correctly, as to the "+long-way+* of the land* 7 His providing that James should pay rent to his mother. 8 His decision as to what was to be done with the home place-- 9 His reply when Correll proposed that all should leave the house--