Skepticism, from Ender and Bean

Although Orson Scott Card's novels have raised some controversy, they contain some passages that have stuck with me and affected my own thinking.

Believed, but the seed of doubt was there, and it stayed, and every now and then sent out a little root. It changed everything to have that seed growing. It made Ender listen more carefully to what people meant, instead of what they said. It made him wise.
- Ender's Game, p. 111

The criminal misuse of time was pointing out the mistakes. Catching them - noticing them - that was essential. If you did not in your own mind distinguish between useful and erroneous information, then you were not learning at all, you were merely replacing ignorance with false belief, which was no improvement.
- Ender's Shadow, p. 87-88

Both quotes deal with the idea of critical thinking - examining information for its value before incorporating it into your own corpus of knowledge. I fear that critical thinking is increasingly devalued in our current society, and even those who wish to understand issues and ideas more deeply are overwhelmed by the glut of information that is available to us nowadays through television, radio, books, newspapers, magazines, the Internet, and (lest we forget) the people we talk to.