梁啟超在《先秦政治思想史》的撰述中，除介紹儒、道、墨、法四家思想之特色，同時也展現了其所關切的中國傳統思想如何在20世紀初與西方文明進行對話。這些對話的內容含括個人與社群之關係孰為輕重？國家主義與世界主義之區別何在？國家經濟與國民生計該如何達到均富之要求？在西方現代文明社會型態之外，中國先秦諸子思想如何提供另外一種生活及價值選擇的可能？上述各項議題，本文嘗試運用「界」與「類」兩種觀念作為詮釋架構，並以之對應儒學倫理相關課題，提出梁啟超在政治上主張「愛類去界」以完成世界主義之理想，在經濟生計方面強調「度量分界」以求均富，而這兩種從先秦儒學發展出來的倫理向度，有助於理解梁啟超在本書結論之中所提出的精神生活與物質生活、箇性與社會性如何調和等課題。

Liang Chichao”Pre-Qin history of political thought”, in addition to introduction the characteristics of the Confucianism, Taoism, Moism, Faism four thoughts, but also demonstrated its concern about the dialogue between Chinese traditional thought and Western civilization in the early twentieth century. The dialogues encompass three items: what is the severity between the relationship of the individual and the community? The differences between nationalism and cosmopolitanism? and how to achieve equal distribution of wealth between livelihood of the country's economic and national requirements? Except modern Western civilization society type, the Chinese Pre- Qin various schools of thoughts how to provide another possible choice and value of life? The above issues, we try to use ”jie” and ”lei” concept as an interpretation framework. Liang Chichao advocated ”love to the world class” in politics in order to complete the ideal of cosmopolitanism, in the economic livelihoods emphasis on ”measurement boundary” In order to get average rich. Both of these two developed from the pre-Qin Confucian ethics dimension, help to understand the conclusions of Liang Chichao in the book made into the spirit of life and material life, and how to reconcile individual and social topics and so on.