Wikiquote:Quote of the Day/January 4, 2009

"Human beings, who are almost unique in having the ability to learn from the experience of others, are also remarkable for their apparent disinclination to do so." – Douglas Adams

Simple: People are almost the only animals that can learn from what others do. Another interesting thing about people is that they do not seem to want to.
What it means: People have the ability to make great changes, but usually they are not willing to.