Oh, and another thing. I would say that rather than accusing the knowledge for destroying the human spirit, I would suspect the desensitization or attention of being the big culprits.

People for example tend to turn to New Age to find some kind of mystery that they can marvel at. This is not because the things that fascinated these people in their childhood have been solved and that they now have knowledge (e.g. Is the universe infinite?). It's because they've come to grow accustomed to the world they see everyday. Things that once were mysteries have become mundane and to get exited over the world, one has to move up, finding something that's a mystery again.

We come to this world, marveling over it's existence. In pace with our growing acquisition of it through perception, we aquire the skill to make more or less accurate predictions about it. The first time you fall in love, the feeling is extraordinary and half of your time goes into wondering how something ever could feel so strong. The second time around you know what to expect and soon, the predictions we make is in accord with the actual outcome, thereby focusing our attention on other things in the world. What once were a great mystery still is, but we learn to ignore it.

Come to think of it, it really comes down to how you define knowledge. My epistemologic view is a quite skeptical one, so I guess this reasoning makes sense for me.