Over the past few decades, the value of an MBA has declined, probably because the academic world can't keep up with the rapid pace of change in the business world.
Relatively few entrepreneurs have MBAs, but I'll bet that almost all of the successful ones have read and truly treasure these seven short, easy-to-read classics:

1. "As a Man Thinketh," by James Allen

What It Teaches: Most people labor under the misconception that their life is the result of fate, luck, or circumstances.
This book explains that your life is what you make of it, and the only way you'll be successful in life is if you're first successful in your mind. This is the foundation of a successful career in business. (It's also one of the top 10 motivational books of all time.)
Best Quote: "A man only begins to be a man when he ceases to whine and revile, and commences to search for the hidden justice which regulates his life. And as he adapts his mind to that regulating factor, he ceases to accuse others as the cause of his condition, and builds himself up in strong and noble thoughts; ceases to kick against circumstances, but begins to use them as aids to his more rapid progress, and as a means of the hidden powers and possibilities within himself."

2. "Rich Dad Poor Dad," by Robert T. Kiyosaki

What It Teaches: In addition to the basics of personal finance (without which success is pointless), this book explains why building and owning businesses is the most reliable way to gain wealth. It destroys the absurd notion that a salaried job represents financial security and shows you how to think like an entrepreneur.
Best Quote: "Mankind is divided into rich and poor, into property owners and exploited, and to abstract oneself from this fundamental division and from the antagonism between poor and rich means abstracting oneself from fundamental facts."

3. "Who Moved My Cheese?," by Spencer Johnson

What It Teaches: Countless books have been written about disruptive innovation and how every individual and company must adapt to an ever-increasing pace of change. No book, however, has explained the situation (and what to do about it) so succinctly and vividly.
Best Quote: "What you are afraid of is never as bad as what you imagine. The fear you let build up in your mind is worse than the situation that actually exists."

4. "The Elements of Style," by William Strunk Jr. and E.B. White

What It Teaches: Now that emailing, texting, and social networking are the core of business communication, the ability to write clearly has never been more essential. After reading this book, you'll be a better writer than you were before and better than your less-informed colleagues.
Best Quote: "Vigorous writing is concise. A sentence should contain no unnecessary words, a paragraph no unnecessary sentences, for the same reason that a drawing should have no unnecessary lines and a machine no unnecessary parts. This requires not that the writer make all his sentences short, or that he avoid all detail and treat his subjects only in outline, but that every word tell."

5. "The One Minute Manager," by Kenneth Blanchard and Spencer Johnson

What It Teaches: If there's a better and more simple definition of what it means to be a good manager, I've yet to find it. This book contains more business wisdom (and ways to put it to use) than a dozen libraries full of academic case studies. Every boss or would-be boss should read this book.
Best Quote: "If you can't tell me what you'd like to be happening, you don't have a problem yet. You're just complaining. A problem only exists if there is a difference between what is actually happening and what you desire to be happening."

6. "How to Lie With Statistics," by Darrell Huff

What It Teaches: A defining characteristic of every business today is the desire to measure. Metrics, however, are worse than useless unless they're interpreted appropriately and fairly. This book puts you wise to all the tricks people use to manipulate the truth so that it leaves a false impression. It's definitely one of the 10 most eye-opening books that every entrepreneur should read.
Best Quote: "The secret language of statistics, so appealing in a fact-minded culture, is employed to sensationalize, inflate, confuse, and oversimplify. Statistical methods and statistical terms are necessary in reporting the mass data of social and economic trends, business conditions, 'opinion' polls, the census. But without writers who use the words with honesty and understanding and readers who know what they mean, the result can only be semantic nonsense."

7. "The Greatest Salesman in the World," by Og Mandino

What It Teaches: If you can't sell your ideas, your product, or your services, you will never be successful in business. You could read dozens of books about selling, but they all come down to the simple truths in this book, which is definitely one of the top 10 sales books of all time. Warning: This book won't just make you more successful in business. It will make you more successful at life, as well.
Best Quote: "I will live this day as if it is my last. This day is all I have and these hours are now my eternity. I greet this sunrise with cries of joy as a prisoner who is reprieved from death. I lift mine arms with thanks for this priceless gift of a new day. So too, I will beat upon my heart with gratitude as I consider all who greeted yesterday's sunrise who are no longer with the living today. I am indeed a fortunate man and today's hours are but a bonus, undeserved. Why have I been allowed to live this extra day when others, far better than I, have departed? Is it that they have accomplished their purpose while mine is yet to be achieved? Is this another opportunity for me to become the man I know I can be?"
Read the original article on Inc.. Copyright 2015. Follow Inc. on Twitter.

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