《资治通鉴·唐纪·唐纪五十》
又因两税处于创立制度的初期，没有追求制度的整齐划一，物资的供应办法有繁琐与简便的区别，州府长官有精明与愚笨的不同，各处的徭役赋税，轻重悬殊，朝廷派遣的使臣，意见各有分歧，但计划上奏，一经决定，就只有增加，没有减除。
复以创制之首，不务齐平，供应有烦简之殊，牧守有能否之异，所在徭赋，轻重相悬，所遣使臣，意见各异，计奏一定，有加无除。
Again, because the two-tax system was in its early stages of establishment, there was no pursuit of uniform standards, and there were differences in the methods of commodity supply, with some being cumbersome and some being simple, and there were differences in the wisdom and stupidity of state and county officials. The corvée and taxes in various places varied in weight and severity, and the opinions of the envoys sent by the court were very different, but once the plan was submitted and decided upon, there was only an increase, no reduction.