Ptolemy, considered a proto-Humanist by some, combined the principles of Northern Italian republicanism with Aristotelian theory in his De Regimine Principum, a book that influenced much of the political thought of the later Middle Ages, the Renaissance, and the early modern period. He was the first to attack kingship as despotism and to draw parallels between ancient Greek models of mixed constitution and the Roman Republic, biblical rule, the Church, and medieval government.

In addition to his translation of this important and radical medieval political treatise, written around 1300, James M. Blythe includes a sixty-page introduction to the work and provides over 1200 footnotes that trace Ptolemy's sources, explain his references, and comment on the text, the translation, the context, and the significance.

托勒密被一些人认为是原人文主义者，他在《统治原则》一书中把意大利北部的共和主义原则与亚里士多德的理论结合起来，这本书影响了中世纪后期、文艺复兴时期和现代早期的许多政治思想。他是第一个将王权作为专制主义进行攻击的人，并将古希腊的混合宪法模式与罗马共和国、圣经中的统治、教会和中世纪政府相提并论。

James M. Blythe除了翻译这本大约写于1300年的重要而激进的中世纪政治论文外，还为该作品撰写了60页的介绍，并提供了1200多个脚注，以追溯托勒密的来源，解释他的参考文献，并对文本、翻译、背景和意义进行评论。