Some of the most profound, insightful thoughts in business aren't that complicated. Heck, a lot of them are clear as day. You might be surprised at how much you can take away from something as simple as a one-line quote. Let's take a look at the first five quotes in this two-part series. 

"I will tell you how to become rich. Close the doors. Be fearful when others are greedy. Be greedy when others are fearful."
Warren Buffett

We all know how warm and fuzzy it feels to watch our stocks go up; that's why we're investing in the first place ... to make money. Alas, the human ego is a powerful thing, and it's when we're doing well in the market that we feel the most invincible, and when the market tanks that we feel like pulling all our money out, curling up in the fetal position, and screaming.

Don't get me wrong. Trying to time the market probably won't get you very far, but that's not the point. If you take a long-term approach to investing, purchasing stocks that have been beaten down and appear cheap based on fundamentals -- while having no expectations as to when they should start heading up -- it will likely leave you sitting pretty down the road.

"Based on my own personal experience -- both as an investor in recent years and an expert witness in years past -- rarely do more than three or four variables really count. Everything else is noise."
Marty Whitman

We're constantly bombarded with endless amounts of trivial pieces of data for our investments. Untold amounts of wealth have been lost in the name of panic caused by complete overreaction to events that, in the grand scheme of things, don't matter a hoot.

Take a company like oil tanker Frontline (NYSE:FRO). Back in 2002, value investor Mohnish Pabrai began purchasing shares after the company had taken a beating when other investors were in panic mode, trying to get their heads around an array of factors, such as where the future price of oil was heading and when oil tanker rates would rebound. Pabrai took a more simplified view and focused on something much clearer: the liquidation price of the company. By focusing his attention on the big, important factors while ignoring the noise around him, Pabrai was able to score a multibagger in just two years. Keepin' it simple has its benefits.

"Never count on making a good sale. Have the purchase price be so attractive that even a mediocre sale gives good results."
-- Warren Buffett

Heck, nobody's perfect. From time to time, even the best investors in the world make mistakes. It's important you don't set yourself up for a complete catastrophe when you do. Companies with large cash balances that make up a significant portion of their market cap, such as K-Swiss (NASDAQ:KSWS), provide a floor on the stock that you may be able to tag the "worst-case scenario" price.

The best situation you can put yourself in is when your investments offer such a large margin of safety that even if you don't end up being right, you'll still turn out OK. It's like playing Russian roulette with a squirt gun.

"The four most expensive words in the English language are, 'This time it's different.'"
-- Sir John Templeton

Every excessive boom in the stock market, whether it's the entire market or an individual stock, seems to share this common characteristic. People know prices are getting out of hand. They know every time this has happened in the past, people got burned. Yet investors can get caught up with the thought that this time, the excessiveness is justified and will be here for good. 

Sure, you can try to say that the outrageous valuations on some Chinese stocks -- such as Chinese search engine Baidu (NASDAQ:BIDU) or the recent trillion-dollar market cap foray of PetroChina (NYSE:PTR) -- are justified because "China is different this time." Yes, China has many positive factors stacked in its favor, but that doesn't come close to ever justifying overvaluation. We'll never learn that we never learn.

"The stock market is filled with individuals who know the price of everything, but the value of nothing."
-- Philip Fisher

Far too many people focus on the share price of their stocks, and have little -- if  any -- knowledge of what they're actually getting for that share. For the same reason that a $1,000 T-shirt is absurdly expensive but a $1,000 new car can be a bargain, you're much more likely to find value in an established company like Berkshire Hathaway (NYSE:BRK-A) (NYSE:BRK-B) at $135,000 a share (or almost $5,000 for its B shares) than you will in some penny stock your neighbor tipped you off to.

There you have it. Some of the shortest, simplest, and most reflective quotes by some of the greatest investors of all time. Check back soon for Part 2 of "The Greatest Investment Quotes of All Time. "

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