張東蓀的西化哲學裡有無處不在的折衷論。這個特色是與Charles Moore 所總結、令人生畏的二十一大點中國思想特徵，尤其是與第十三、第十四點關於中國折衷論的描繪一致的。 張東蓀思想中西化性質可以分三個層次來處理。第一個層次，是關於他讀過的西文書，這是最無爭議但比較不深刻的證成法。第二個層次，是關於他費力從事於「介紹」，或比較正確地說，改換西方觀念、信條和學派以適應中國的環境和需要。第三個層次，是關於他基於對這些有所改變的西方觀念、信條和學派而企圖建立和鼓吹的哲學體系。 本文在介紹了張東蓀哲學裡無疑的西化特色或西化性質後，將會集中在其中的折衷論。在張東蓀的眼中，折衷論確是處理中、西方哲學、思想與文化交往時比較理想或可取的態度、步驟、方法和原則。他為了折衷常不得不斷改變看法，而看法若改變了，也不得不加以折衷。 基於把張東蓀看成可能是「最西化的」現代中國哲學家或思想家的論斷，本文的目的，即是要進一步詳細展示，張東蓀的折衷論到底可以證成至何等程度。

Eclecticism is ubiquitous in the highly westernized philosophy of Chang Tung-sun [Zhang Dongsun]. This feature is in accord with the thirteenth and fourteenth points about Chinese eclecticism as enumerated by Charles Moore in his formidable list of twenty-one notable features of Chinese thought. The westernized character of Chang’s thought can be dealt with on three levels. The first level concerns western books he read (or even merely consulted), which rests on a straight-forward but superficial methodology. The second level concerns his strenuous efforts to “introduce” western thought, or more properly speaking, his transformation of western ideas, doctrines, and schools of thought for the sake of meeting China’s environment and needs. The third level is closely related to Chang’s establishment and advocacy of philosophical systems on the basis of such a heroic transformation. After having dealt with the undoubted westernized character in Chang’s philosophy, this article then focuses on his eclecticism as the crux of his whole thought. From Chang’s point of view, eclecticism is itself an ideal or preferable attitude, approach, method, and principle for dealing with the intercourse between Chinese and western philosophies, thought, and cultures. This article highlights how, to fulfill this ideal, Chang consistently had to change his views, which in turn affected his eclecticism in an open-ended way throughout his life. Taking seriously the argument that Chang probably was “the most westernized” Chinese thinker of his day, this article is designed to examine precisely how his eclecticism was central to his philosophy.