Earlier this month, we examined eight quotes that could make you a better investor. Those nuggets of wisdom came from people who found their fame in places outside the investing realm.

But why stop with just eight? Let's keep the party going! Here are eight more quotes for you to ponder.

"He who wishes to be rich in a day will be hanged in a year."
-- Leonardo da Vinci

Yikes! Grim as it sounds, da Vinci's advice holds true in investing. I won't bore you with the facts about how Altria (NYSE:MO) would make you rich beyond belief if you held it patiently for half a century. Everyone knows how compounding works. But when a company really takes off in a jiffy, more often than not it corrects in just as grand a fashion. Look no further than Crocs (NASDAQ:CROX) or China Finance Online (NASDAQ:JRJC) for proof. Big fortunes can be made in short order, but they can be lost just as quickly if you're not careful.

"If at first you don't succeed, try, try again. Then quit. No use being a damn fool about it."
-- W.C. Fields

Good advice, if taken the right way. Some investors who go at it alone have an asinine way of outsmarting the market that makes a Ouija board look smart. If the results from investing on your own don't speak for themselves, there's no shame jumping in with the herd and using mutual funds and ETFs to invest. Not everyone can be Warren Buffett, after all.

"Opportunity often comes disguised in the form of misfortune, or temporary defeat."
-- Napoleon Hill

It shouldn't surprise you that some of the best returns come after periods in which investors wouldn't touch anything with a 10-foot pole. After the carnage of the past year, particularly in financial and housing stocks, don't be shocked if two or three years hence the biggest winners come from names such as Wells Fargo (NYSE:WFC) and NVR (NYSE:NVR) -- companies that have been punished as of late but stand out from their wayward peers.

"As I grow older, I pay less attention to what men say. I just watch what they do."
-- Andrew Carnegie

When reputation can mean the difference between a company's life and death, people will tell you what you want to hear. Bear Stearns CEO Alan Schwartz was trumpeting his company's ability to stand strong just days before it fell into JPMorgan Chase's (NYSE:JPM) hands. His words may have very well been true. But what really mattered wasn't what anyone said. It was what was happening behind the scenes -- and in this case, hedge funds and other larger investors were pulling money out en masse. Ignoring the words of those whose incentives might be a little skewed, and focusing instead on what they do, such as engage in insider buying and selling, will usually separate the truth from the trash.

"I have hardly ever known a mathematician who was capable of reasoning."
-- Plato           

Save the hate mail, mathematicians. Bear with me while I make a point. Some of the greatest geniuses have completely bitten the dust in investing because their minds couldn't travel outside the wonderful world of math. Back in 1998, a hedge fund called Long Term Capital Management -- whose ranks included Nobel laureates -- completely imploded after events took place that its mathematical models had showed were nearly impossible. Numbers can't think. They can't ration. They can't reason. They're there to assist you in your pursuit of good investments, which should be fueled by as much qualitative as quantitative analysis.

"Life is simple, but we insist on making it complicated."
-- Confucius

Buy good companies. Don't pay a lot for them. Hold them for a long time. This isn't rocket science, but achieving stellar results eludes many of us simply because we attempt to outsmart the market. Day trading, market timing, and a number of other snazzy techniques typically leave investors far behind in the long run.

"The moment a person forms a theory, his imagination sees in every object only the traits which favor that theory."
-- Thomas Jefferson

Back in 1999, Wharton professor Jeremy Siegel wrote a piece for The Wall Street Journal that highlighted tech stocks' insane valuations. He used AOL, now part of Time Warner (NYSE:TWX), as an example.

In defense of AOL, a reader responded:

Good morning, Mr. Siegel. I hope you're happy. ... What do you have against this mammoth company? Are you jealous because you didn't get in on the run-up? Did you want to buy in cheaper? You have no business making decisions like this. After all, you're still a child when it comes to Internet knowledge. You're a preschooler in diapers when it comes to recognizing opportunities.

Never mind that Siegel was spot-on. The writer was clearly delusional about AOL's prospects as an investment. When euphoria -- or fear, for that matter -- clouds an investor's perception of stocks, reason can go straight out the window. Pity the person who tries to lend a helping hand.

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