  We construct a model where people trade assets contingent on an observable
signal that reflects public opinion. The agents in our model are replaced
occasionally and each person updates beliefs in response to observed outcomes.
We show that the distribution of the observed signal is described by a quasi
non-ergodic process and that people continue to disagree with each other
forever. Our model generates large wealth inequalities that arise from the
multiplicative nature of wealth dynamics which makes successful bold bets
highly profitable. The flip side of this statement is that unsuccessful bold
bets are ruinous and lead the person who makes such bets into poverty. People
who agree with the market belief have a low expected subjective gain from
trading. People who disagree may either become spectacularly rich, or
spectacularly poor.
