如果「存有的前提」與「認識的前提」之區別是合理而根本的，則必須進一步追問二者間的關係。就邏輯而言，兩者間之關係只能有三：1)兩者不可化約，2)可以「存有的前提」取代「認識的前提」，3)可以「認識的前提」的取代「存有的前提」。此三者在哲學史上各有康德與馬克思、黑格耳語盧卡奇可為其代表。對三者的詮釋，最後導引出一更為基本的問題：是否有「現象」與「本質」之差別？

　　　　　If a distiction between ontological and epistemological conditio sine qua non is resasonable and essential, it is than to ask the relationship between them. From logical point of view on the one hand there is only three positions possible: 1)these two kind of condition are irreducible, 2)the ontological one can be reduced to the epistemological one, and 3)vice versa. From historical point of view on the other hand, Kant and Marx, Hegel and Lukacs could be taken respectively as exponents of these three positions. An interpretation of their positions leads to a question which stands behind: whether the distinction between "phenomena" and "essence" is acceptable?