Here are 30 one-sentence lessons I've learned since then:

1. Prices always correct themselves, even if it's years in the making.

2. The government will bail out institutions before they bail out retail investors.

3. You can "buy the market" and still underperform if you don't have your emotions in check.

4. Investors who constantly lose money do so because they're speculating, not investing.

5. Stock market bubbles can create tremendous wealth, but they can take it away just as fast.

6. The more analysts hype stocks, the more money they make.

7. 95% of people cannot beat the market long-term, but 99% of people shouldn't try to begin with.

8. It doesn't matter how great of an investor you are, you can always be wrong.

9. The market won't always be efficient and when you exploit this you profit.

10. Stock picking works, it's just extremely difficult to be good at it.

11. Stock picking used to be harder when information is scarce, but now information spreads quickly, even to retail investors.

12. There will always be a market for people who predict stock prices.

13. There are only 2 reasons to sell an investment and they have nothing to do with the price.

14. Forecasting earnings will be your bread and butter for analyzing stocks.

15. It's the nature of average returns that some investors will be above-average.

16. There's no premium for bearing risk that can be diversified away.

17. Investors tend to consider themselves better than they actually are.

18. Just because a lot of people agree that a stock price will rise, doesn't mean it will.

19. Losing money in stocks hurts more than the pleasure of making money in them.

20. Investors are more likely to sell winners and hold on to losers, but the opposite is how to make money.

21. The market can remain irrational longer than you can remain solvent.

22. Hot stocks don't stay hot forever.

23. Losses cushion your tax obligation and winners add to it.

24. It's possible to make money in stocks whether the market is up, down, or sideways.

25. It's easier to go broke than it is to build wealth and that's why most people aren't wealthy.

26. Saving will never make you wealthy.

27. Only take as much risk as you're comfortable with and make sure that risk is worth the reward.

28. 90% of your returns are determined by the asset class and 10% are determined by the specific holdings.

29. Cash isn't always bad, even in an inflationary environment.

30. A bear market is the best thing that can happen to a long-term investor's portfolio".

Kilde: @WOLF_Financial på Twitter