《荀子》全書提及「知」/「智」高達四百八十七次，顯示對「知」/「智」的高度重視。本文對《荀子》中的「智」德/「智德」思想研究也必須同時透過「知」與「智」的分析與了解。荀子突顯「心」－尤其南「解蔽心」－的認知義是極為特殊的，「智」德/「智德」也在道德知識論的特殊建構中呈現，形成《荀子》「智德」思想之一大特色。「知」(讀為ㄓ)首先作為「人」此一存在階層的特殊能力－認知能力，「心不可以不知道」故，「道」作為「知」的主要對象。其次，「知有所合謂之智」故，「知識」作為「智」的第一個意義；「是是非非」則是「知」(讀為ㄓˋ)/「智」的第二個意義，也是智德的主要內涵。至於作為與仁德對舉之知(智)德，於孔孟儒家，並非只是作為輔「仁」的次德，而是與仁德等量齊觀的主德；其內涵除了「是是非非」外，範圍以「自知」為基礎，進而「知人」、「使人知己」；因而有「智」的不同等級之分。最後，結論出荀子「智德的意義與價值」在於：除了承接孔孟對智德思想的重視外，更進一步將「知」/「智」提升為整個道德實踐論的知識論基礎建構中之核心概念。

　　　　　The term “chih (知/智, intellect)” is found in Xun-zi for four hundred and eighty-seven times, showing the term is highly valued. In this article, the research on the concept of “prudence (practical wisdom)” also needs to be made through analyzing and understanding “chih (intellect).” Xun-zi stresses that the cognitive meaning of “mind” especially “revealing the mind(Chieh-pi hsin, 解蔽心)” is extremely specific, and prudence is also manifested in the special construction of moral epistemology, which is a major characteristic of the thought about “moral intellect” in Xun-zi. “Chin(知, intellect)” is firstly a special capacity-cognitive capacity at the level of human being, while “Tao(li-yi,禮義之「道」 )” is the major object of “intellect.” Moreover, knowledge is the first meaning of “chih(智, intellect)”, while “right and wrong” is the second meaning of “chih(智, intellect)” as well as the primary immanence of “prudence.” As the counterpart of moral humanity, moral intellect is not, as in Confucianism, a secondary virtue subsidiary to “humanity” but a primary virtue equivalent to moral humanity. The immanence of prudence consists of “right and wrong” and ranges from “knowing one's self” to “knowing others” and “making others know one's self”, therefore intellect or prudence is graded. Finally, it's concluded that the meaning and value of Xun-zi's prudence lies in: other than continuing Confucius's and Mencius's emphasis on prudence, promoting “chih (知/智, intellect)” as the under-cnostruction key to the espisteemological foundation of the whole theory of moral practice.