The final Confucian thinker of the classical period to be discussed here is Xunzi, or Master Xun, whose given name was Xun Qing. His dates are uncertain, but he was probably born a few years before Mencius died (the end of the 4th century BCE), and he lived roughly until the time that the Qin dynasty reunited China in 221 BCE. So he was able to look back at the entire extent of the Warring States period and survey all the philosophers who came before him. He was also intimately involved with the intellectual currents of his time, as he was a leading figure at the Jixia Academy -- a kind of think-tank in the state of Qi.
Xunzi was a sceptical, rationalist thinker, who nevertheless argued forcefully for the importance of ritual. He is mainly known for his theory, directly contradicting Mencius, that human nature is evil. But as we shall see, Mencius and Xunzi had more in common than their differences. His book, unlike those of Confucius and Mencius, is not a record of conversations but a series of essays, each on a single topic. Here we shall discuss only a few of them.
On Heaven (ch. 17)
In Xunzi=s essay on Heaven, he departs radically from the ideas of Confucius and Mencius. In fact, he refutes the doctrine of the Mandate of Heaven by saying that Heaven does not care about human affairs. Heaven, for him, is nothing more than the natural world; it has no moral will, and its activities are entirely unrelated to human activities. Those who pray for rain, for example, are wasting their time. Those who believe that comets and other extraordinary natural events indicate Heaven=s displeasure with those in power are foolish. AOnly the sage,@ he says with deliberate irony, Aacts without seeking to understand Heaven.@ 
Xunzi=s attitude toward Heaven is more than just scepticism. His real point is that human beings are in control of their own destinies; we must not fool ourselves into thinking that Heaven can intervene to help us or that Heaven is responsible for our troubles. True, he says, natural events such as floods or droughts are Heaven=s doing, and they certainly affect us, but they have no inherently human meaning. Heaven is responsible for how things are (the realm of facts), not how they ought to be (the realm of values). Heaven, Earth, and Mankind are three independent spheres of activity, Heaven and Earth being morally neutral. We must live with the effects and limitations imposed on us by Heaven and Earth, but essentially our lives are what we make of them. Therein lies the real challenge, for Xunzi, and in that respect he is completely in agreement with Confucius and Mencius.
On Ritual (ch. 19)
Despite his departure from a formative Confucian doctrine, Xunzi was a devoted follower of Confucius. He laid great stress on education, self-cultivation, statecraft, and formal ritual. His theory of ritual, in particular, was one of his great contributions to Chinese thought. He said that the formal rituals, especially those practiced in ordinary life, such as marriage, funerals, and ancestral sacrifice, were devised by the great Sages of the past in order to embellish or adorn human life by giving us structures through which we can fully develop and express our natural emotions. Such feelings as joy, grief, and reverence are distinctly human characteristics, and so to fully realize them is to be fully human. Ritual is a means of bringing into existence a fully human world from the raw material of our emotions; it is a means of satisfying certain psychological needs and desires without encroaching on those of others. Only the ancient Sages could have achieved this delicate balance.
Xunzi=s astute psychological insight is evident in his discussion of sacrifice:
Xunzi=s theory of repression clearly anticipates Sigmund Freud by over two millennia. In the last sentence he also makes an interesting point concerning ritual and belief. Since the Sages had a psychological purpose in creating the rituals, their efficacy does not depend upon belief in the existence of ancestral spirits or their ability to respond to sacrifice. Common people believe in those things, but a junzi understands their importance and efficacy in psychological, not theological, terms. In this respect and others, Xunzi sounds extremely modern to our ears.
Human nature is evil (ch. 23)
Xunzi=s most famous essay begins as follows:
Notice that Xunzi does not refute Mencius= claim that human beings are born with certain emotions that can lead to morality. So why, then, does he come to the opposite conclusion about human nature? He is quite explicit about his disagreement with Mencius:
This passage holds the key to the disagreement between Mencius and Xunzi: they have different understandings of the general concept of the nature of a thing (xing). Recall that Mencius= implicit understanding of the nature of a thing seemed to be that it is something that is innate and unique to that species. Since moral inclinations or moral potential fits those criteria, that constitutes human nature. But Xunzi defines the term as that which is innate and does not require effort to complete. The fact that Mencius= Afour beginnings@ must be cultivated rules them out of consideration. For Xunzi, only innate and spontaneous developed traits can count as human nature. And what fits this bill are the selfish, violent emotions, not moral inclinations. While Mencius is clear about offering a theory of potential goodness (above, 6A:6) -- recognizing that moral potential, in the form of the four beginnings, is something that actually exists and is not mere possibility -- any human trait that spontaneously appears only in potential form cannot be considered human nature for Xunzi. Thus the claims about human nature made by Mencius and Xunzi are like ships passing in the night.
So the fundamental difference between Mencius and Xunzi on this point concerns their definitions of the word xing, which lead them to look for psychological traits fitting different criteria. But do they really differ in their theories of human personality? They both acknowledge that human beings have both bad or selfish emotions and good ones. And more importantly, they both believe in the moral perfectibility of human beings. The difference between them on this score is that for Mencius it is a matter of cultivation or nourishment, while for Xunzi it is a matter of transformation. Without the external influence of sages and teachers to effect that transformation, human beings continue to indulge their selfish and violent emotions. Like warped wood that Amust be laid against a straightening board, steamed, and bent into shape before it can become straight,@ only exposure to the teachings and rituals of the sages and moral examples of teachers can counter this natural tendency.
Thus, for Xunzi, education is even more important than it is for Mencius; it is the only counterforce to the natural tendencies that lead to competition, strife, and aggression. But this, of course, raises the questions: what is the ultimate origin of goodness? Xunzi=s answer is that Aritual and rightness are always created by the conscious activity of the sages: essentially they are not created by human nature.@  Sages create ritual and rightness like a potter molds a pot, or a woodcarver creates a tool: not from their own natures, but by transforming some raw material into something new. The nature of a sage is the same as the nature of anyone else, and so Athe man in the street can become a Yu.@ Why then do ordinary people need external help to become good?
Xunzi does not give an explanation of the difference between the sage and the ordinary person, the crucial factor that allowed sages -- particularly the first sages -- to overcome their evil natures. This is a serious weakness in his theory. A good environment would suffice to explain how later people could become good, but not how goodness (ritual and rightness, etc.) originated. Fourteen centuries later, the Neo-Confucian thinker Zhu Xi would fill in the gaps in Xunzi=s theory -- although he considered himself a follower of Mencius.
 Trans. Irene Bloom, Sources of Chinese Tradition, ed. Wm Theodore de Bary and Irene Bloom (NY: Columbia University Press, 1999), 2nd ed., vol. 1, p. 171.
 Sources, p. 177.
 Sources, p. 180.
 Sources, p. 180.
 Sources, p. 181.
 Sources, p. 182. Mencius said basically the same thing (6B:2).