United States tax law attempts to define a comprehensive system of measuring income in a complex economy. Many provisions defining income or granting or removing benefits require significant definition of terms. Further, many state income tax laws do not conform with federal tax law in material respects. These factors and others have resulted in substantial complexity. Even venerable legal scholars like Judge Learned Hand have expressed amazement and frustration with the complexity of the U.S. income tax laws. In the article, "Thomas Walter Swan", 57 Yale Law Journal No. 2, 167, 169 (December 1947), Judge Hand wrote: