[sdfx]

I think the no-arbitrage principle comes into play as well: If there is an (easy) set of rules that you can follow to make money, then there are enought people to act according to these rules so that you can't win anything. Seriously, this simplistic view of the market is just a threat to your hard earned bucks.

There are historical prices available at finance.google.com. Backtesting your strategy before playing around with real money is probably a good idea.

[matt1]

Again, that assumes that the future can be predicted using past results. Even if you had an algorithm that seemed to predict the dips and peaks in the market, it would not be a good predictor of future performance.

I recommend Random Walk Down Wallstreet or Fooled by Randomness or, if you really want a brutal introduction to randomness, play and study the mathematics of poker.

[wildwood]

How high to you have to jack up a) the number of people who believe in this principle, and b) the number of simple ways to make money (possibly multiplied by the number of available markets), before this principle is no longer true?