10 Simplified Investment Management Principles

Here is the article.

1. Diversify
2. Stay the course
3. Invest for the long term
4. Focus on what is in your control
5. Rebalance regularly
6. Maintain liquidity
7. Accept normal market volatility
8. Invest incrementally
9. Noise is not a plan
10. Monitor your behavior 

Dean Witter

It takes courage to be optimistic about the future when pessimism abounds, but when the future is again clear, today's bargains will have vanished. 

Invest incrementally over full market cycles rather than attempting to repeatedly a market bottom. It is better to be generally right by investing consistently over time, rather than precisely wrong by investing all at once. 

Plunge. Soar. Optimism. Panic. Greed. Trigger words and sensational headlines may cause investors to make irrational decisions, but market timing is folly.

Warren buffet

The most important quality for an investor is temperament, not intellect.