牟宗三先生曾說康德在西方無「善紹」 ，而當代西方康德學家安默瑞克斯（Karl Ameriks）也說： 「那位本來無後的教授，形上學家康德：留下一窩非法的子嗣。」 如果用牟先生的詞語說，這 「一窩非法的子嗣」 都是 「別子」 ，間接也就是無「善紹」的意思。
牟先生認為康德太客氣，把「智的直覺」只歸屬上帝，上達的路徑太虛歉，所以他從中國哲學「實踐」的立場，把「智的直覺」歸給人類，消彌「現象與物自身」的二分，還出一個以「價值」為皈依的「絕對實在論」 。而安默瑞克斯則以為康德哲學原是一個比較樸素的系統（modest system） ，卻因萊因赫德（K. L. Reinhold）鼓吹「實踐理性的優先」 ，而使原來樸素的哲學轉為黑格爾的絕對理念論，不但轉化了康德，也侵蝕了康德。但是英語系的發展，卻因萊因赫德的《書信》 （Letters on the Kantian Philosophy）不曾被譯成英文，而沒有發展出德國理念論的型態，反之，英美系循《第一批判》的另一條線索，追究嚴格的科學（exact science） ，發展出邏輯實證論、科學實在論及實用主義等說，這其中被流失的，正是康德哲學樸素的原味，這個原味由耶拿一批名不見經傳的早期浪漫派學者所繼承（early Romantics） ，可惜他們完全被後期浪漫派的光芒所掩蓋，這是康德哲學的不幸。
本文有意藉安默瑞克斯對康德哲學樸素的詮釋，對比牟先生對康德哲學的轉化，指出牟先生與西方康德後學之同異，並勾繪康德後學是「別子」還是「善紹」的輪廓。

Professor Mou Zongsan once proclaimed: Kant has no great successors
in the West. Recently, Professor Karl Ameriks also uttered: A supposed
childless professor, Kant the metaphysician left behind a fertile family of illegitimate heirs. By contrasting Mou’s and Ameriks’ perspectives
employed to express a somehow shared sentiment, this paper intends to
extract the philosophical imports from this seemingly mere sentiment taking place in the history of philosophy..
Mou believes that Kant is often too polite to attribute intellectual
intuition exclusively to God. Instead, Mou, by taking the stand of Chinese practical philosophy, attributes intellectual intuition to humans, thus dissolves the gap between phenomena and thing-in-itself and further establishes an absolute realism based on values. Ameriks, on the other hand, thinks that Kant’s philosophy is apologetic and modest in comparison to its direct successors in German Idealism. The transformation of Kant into the German Idealism through advocating the primacy of practical reason by K. L. Reinhold, however, also misunderstands Kant's very basic discourse of critical philosophy. On the other hand, in the absence of English translation of Reinhold’s Letters on the Kantian Philosophy, the Anglo-American Kantians, get Kant’s philosophy expressed in a completely different direction. By following the thread of exact science, they convert the Kantian philosophy to logical positivism, scientific realism and pragmatism, and thus miss the critical flavor of Kant's original insights. Only the early Romantics, in Ameriks’ view, have inherited Kant's critical philosophical thinking.