"If your data set has only one observation it doesn't provide much evidence. That's what the core of the anthropic principle is about." No, the anthropic principle is a bout selection bias.

If everyone who does Forex trading reports the results on the internet, then when I see someone reporting that they made money doing Forex, I should update my confidence that Forex trading is profitable. But if only people who make money in Forex report their results, then my update should be much smaller when I see someone reporting that they made money.

Side note: Chrome spell checker flags "anthropic" but not "Forex". I find that sad.