Hope vs. Belief, Part 1 - Gambling is Good
I hope that John Kerry wins the election. As a libertarian, I want a government that trips over its own feet as much as possible, hence I want the executive and legistlative branches controlled by different parties. Bush's budget bloat is the sort of thing that results from a unilateral government. So, as the Republicans will almost surely retain control of the House and Senate, I hope for a Democratic President.
Yet I believe that George Bush will win the election. It is very hard to beat an incumbent, especially one who inspires patriotic fervor. Its true that he inspires hate too, but I am not convinced that this effect is sufficient (or even greater).
I voice my hopes in political conversations with likeminded friends. I voice my beliefs on the Tradesports market, where I've bet on Bush, currently a 7:6 favorite. These different forums draw out different parts of my opinion about the election: who I want to win vs. who I think will win.
Voicing an opinion is costless - anyone can argue that socialism is great, or that the government won't really inflate a fiat currency. Having a false opinion may be costless if it doesn't affect your life much, and it can produce a benefit of feeling good. So people may choose an opinion based on how it appeals to their hopes, rather on on what they believe is true.
An example of a more incentive compatible system is gambling. While people often gamble irrationally, gambling still tends to draw out more beliefs and less hope than mere discussion. By placing a wager, you tie your opinion to a personal gain or loss, so you care whether you are correct. Hence "Wanna bet?" really means "Do you actually think that, or are you just saying it?", and its a great way to call the windbag's bluff. People offer absurd opinions much more often than they make idiotic wagers. (There are many prophets of environmental apocalypse, but only Paul Ehrlich accepted Julian Simon's bet.)
There is nothing wrong with having hopes - I happily voiced mine above. The problem comes when we confuse our hopes and our beliefs, planning or making decisions based on what we want to be true, not what we believe to be true. In part II, we'll see how this comes into play in politics, where different systems elicit different combinations of hope and belief.
 There is another gain from gambling, and that is more precisely stated propositions. When arguing about exploitation, a libertarian might assume a balanced market, while a socialist might assume a massive power imbalance favoring employers. Its easy to ignore these important details and argue past each other, but when you make a bet, it becomes worthwhile to figure out the exact terms of the wager. It then often turns out that the apparent disagreement is based on different assumptions, and that there is not actually enough disagreement to find a bet which is acceptable to both parties. This makes sense, because disagreements are more likely over matters which are hard to test.