OK, that was a bit depressing, so let's take a look at some of the benefits of cynicism:
1) Cynics are usually right.
When Hurricane Katrina was about to hit New Orleans, many people believed the government would take care of them. Others felt it was best not to leave their safety in the hands of the authorities.
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Hundreds of buses, perfectly capable of evacuating everyone, were left idle. If more people were cynical about the ability of the government to take care of people, perhaps fewer people would have died.
Hmm... that was pretty depressing too. But the good news is that by being more cynical, you can protect yourself from the incompetence, recklessness, and malevolence of other people.
2) When cynics are wrong, it is usually a pleasant surprise.
OK, I'm having a hard thinking of examples for this one. Wait, here we go: honest cabbie returns $4 million violin. Bravo, sir.
It seems to me that most of the world's scoundrels, be they con-artists, politicians, or religious leaders, thrive on the trust of other people. We should all strive to be more cynical.