If you have not realized it yet, trading has a lot of common with gladiating (in case the verb does not exist, let us coin it on ET and spread it to the world "from this place and time" as JFK said once). Wall street is ancient rome, and you the trader is a gladiator. You have cuts to prove it, and hopefully the bankroll of a champion. It does not matter which camp you are on, each day swords are aimed at your head to make it roll. You can defend yourself, but in the long run you need a sword with many edges to make head rolls--- the heads of Benjamin Franklin and co that is, on the back of their greenbacks staring at the inside of your wallet which is inside your deep pocket. The mantra of the gladiator, the modern that is, is to hit them where it hurts the most: their pockets! The rest is just details. For this you need swords with multiple edges. Build the edge of your swords is what I want to discuss and write about here. Hopefully you can join, and tell us a little bit about your battles, you edges, and how you build them. You can toss in there examples of heads that rolled before you, even if you did it just on paper. If Walt Disney can do it and crowds cheer them for it why shouldn't you! There are three types of edges (you can subclassify of course and have other types): 1. The certain edge. This means that your edge will cut your opponent but never cut you, and you are certain. 2. The probabilistic edge. The one that cuts you and your opponent. But over all, which means multiple fights with your opponent, you end up bleeding less than him, and you win at the end. 3. The almost certain edge. Is the edge in between 1. and 2. It is the edge that you can rely on and have proof, that with a probability of almost one, you will win on each trade. But it is not certain. All the above types of edges exist. Now how one can go about finding such edges? Your best friend is: Same causes lead to same effects is a scientific principle. This requires one to think under the surface, and present a logical explanation. Then one uses numbers to ascertain whether or not one has a correct thesis. This usually leads to an edge of type 1 or type 3. What if you did not have the luck/skill to build a model of causes and effects, or just want to reduce your search time for such solid edges? Answer: 1. Find correlations between a variable A and a variable B. 2. If there is a correlation (negative or positive) and this correlation is strong, then B may probably explain (in part or in total) A, or vice versa. 3. Once you have your correlation, you need to establish whether there is a cause and effect relation between A and B. If step 3 does not lead to anything, you are at your own risk to use the result in step 2 to build a trading system. In my view that is what I consider as a gambling trading system. You can win of course, but it is just because you worked things in a way the odds/rewards are in your favor, and not because you really have something fundamental behind your trading. If the climate change, your whole gambling system turns the other way, and you become the gambler and your opponent the house while in your head you are still under the illusion that you are the house. So you have to be sure you are always the house in a gambling trading system. You may also have to deal with the potential moral dilemma that comes with such realization. I can go into further details, but i just wanted to provide a framework with the aim to spark things up and with the hope of getting others to respond and contribute. I just wrote these comments while taking my breakfast, so please ignore things that are not of your taste such as typos, comparisons you do not like, etc.