The Concrete vs. the Abstract.
Dick Yates, the jolly Governor of the Suckers, tells that he called on Uncle Abe one morning when he was trying to get the 88,000 "Hundredazers" accepted, and that during their interview Uncle Abe remarked: "Yates, I'll tell you the difference between the concrete and the abstract. When the Senate passed a resolution requesting me not to appoint any more Brigadiers, as the vacancies were all full, that's the concrete. But when a Senator comes up here with a long petition and a longer face, requesting me to make a brigadier out of some scallawag of a friend of his, as it happens every day—I call that the abstract."