On May 21, 2005 David Foster Wallace gave a commencement speech at Kenyon College, and is the only public speech Wallace gave detailing his outlook on life. It's probably one of his most read pieces, and was posthumously published in a small book format (although I think the format doesn't do justice to what was intended to be a speech). In it, he argues, quite beautifully, against “unconsciousness, the default setting, the rat race, the constant gnawing sense of having had, and lost, some infinite thing.” He begins with a parable:
"There are these two young fish swimming along, and they happen to meet an older fish swimming the other way, who nods at them and says, 'Morning, boys. How’s the water?' And the two young fish swim on for a bit, and then eventually one of them looks over at the other and goes, 'What the hell is water?'"
Here's the audio, as no known video exists: