Author James Collins asked Stockdale how he survived for so long. This is an excerpt of his article:
“I never lost faith in the end of the story, I never doubted not only that I would get out, but also that I would prevail in the end and turn the experience into the defining event of my life, which, in retrospect, I would not trade.
However, later on Collins asked about those who didn’t make it–those who died in captivity. Stockdale replied,
Oh, that’s easy, the optimists. Oh, they were the ones who said, ‘We’re going to be out by Christmas.’ And Christmas would come, and Christmas would go. Then they’d say, ‘We’re going to be out by Easter.’ And Easter would come, and Easter would go. And then Thanksgiving, and then it would be Christmas again. And they died of a broken heart.
This creates a seeming paradox, as most people think that optimism and faith are identical. To this, Stockdale replied,
This is a very important lesson. You must never confuse faith that you will prevail in the end—which you can never afford to lose—with the discipline to confront the most brutal facts of your current reality, whatever they might be.
http://treeofmamre.wordpress.com/2014/01/10/the-vanity-of-optimism-and-the-power-of-faith/