Transcript of the commencement speech given by David Foster Wallace in 2005 at Kenyon college.
He sums up the value of education and critical thinking in this one paragraph
The point here is that I think this is one part of what teaching me how to think is really supposed to mean. To be just a little less arrogant. To have just a little critical awareness about myself and my certainties. Because a huge percentage of the stuff that I tend to be automatically certain of is, it turns out, totally wrong and deluded. I have learned this the hard way, as I predict you graduates will, too.
A sense of humility and acknowledgement that we could be wrong is invaluable for a civilised existence.