本文的出發點是站在道德的經驗面上，討論生物的基因層面和生物演化是杏會影響人類道德意織層面的自利或利他行為，主要焦點是從人類社會實然面中，如何發展道德應然性。本文所討論的當代三種取徑，基本上都反對道德先驗性，主張實然與應然是相關，可跨越的，此三種觀點分別是：以基因決定論為主的「倫理學自然化」(Reductive Naturalized Ethics )， 如 E. Wilson Dawkins(selfish gene)、Michael Ruse 和 R. Alexander。顧名思義，「倫理學自然化」主張「應然」是由「實然」而來，更甚者是，道德行為是由不為意識所察覺的生物基因層面所決定。第二派觀點是 H. Rolston 為代表，他也是從基因和道德的關係上主張「非還原的倫理學自然化」（Non-reductive Naturalized Ethics），又可稱為「顯現倫理學」 (Emergent Ethics) 。「顯現倫理學」 雖是肯定基因是人類構成之基本要素，但是強調在基因構成條件下，人類可以超越基因層次，(顯現) 發展出普遍價值觀與客觀道德原則。就「實然」 是「應然」 關係而言，「顯現倫理學」強調「應然」 的主導性，更暗示著「實然」 是具有「價值觀」 的，只是自然界的「價值觀」和人文社會的「價值觀」是不同的。

　　　　　At the beginning of the twentieth century, G.E. Moore claimed that there is no relation between "what we ought to do" and "what we do do". To conflate the two is to commit the naturalistic fallacy. A century passed by, with the advancement of biology, genetic technology and HGP, the biologist-philosophers are allured to transgress is/ought boundary. They question the legitimacy of is/ought boundary, and problematize following issues, namely, should ethics takes what happen in our genes seriously? Is biology(natural selection, evolution) relevant to our moral reasoning? Morevoer, if cognition is made possible by a priori conditions, in analogy, does moral reasoning also has its a priori conditions? In other words, does the way people actually make moral judgments pre-conditions what good moral judgments are? This paper is about transgression. There are three alternatives all based on the natural history of morality, and they all reject rules-following, base of cognition, morality as well. The three alternatives I discuss in this paper are: ([]Reductive Naturalized Ethics represented by E. Wilson, R. Dakwins and R. Alexander, (2) Non-reductive Naturalized Ethics (Emergent Ethics) represented by H. Rolston; and (3) Postmodern emergent Ethics represented by P.Churchland, 0. Flanagan and P. Bourdieu. In order to discuss the characteristics of each alternative, and to compare their relative theoretical advantage and disadvantage with each other, I focus my discussion on the genesis of altruistic behavior(generosity in particular) , with the