As pointed out by msvan, the quote is actually by Xunzi. Here is the original text in Chinese:

不闻不若闻之， 闻之不若见之， 见之不若知之， 知之不若行之； 学至于行之而止矣

I know what you are thinking `Why would you post something in Chinese? How could non-Chinese speakers understand?' and the reason is I want y'all to check out this super cool add of for Firefox: https://addons.mozilla.org/en-us/firefox/addon/perapera-kun-... With this plugin, the meanings of the words show up onmouseover and you can pretty much get the meaning.