Formal education will make you a living; self-education will make you a fortune.
– Jim Rohn
I just found the quote above and it is very true. If you look at the great entrepreneurs most of them were self starting and self taught. Many such as Gates, Branson, Rose, Karp and Zuckerburg dropped out of college or didn't go to college at all. College will help you to understand how the world works now, but only rarely will it teach you about what is to come or what is happening at the fiery leading edge of real innovative thought.
Entrepreneurs are by nature confident in their own abilities and don't need any outside affirmation or degrees to bolster what they do. They just go out and do it.
Taking the formal education route in business (esp. MBA's at Ivy League schools) will leave you burdened with debt that will cripple your ability to be truly innovative. The money spent on formal education could have been diverted into developing your own business or furthering your innovations.
I am not against formal education as I have graduate and post graduate degrees but I have learned more on how to succeed by self education and learning from business projects that stretch my skills and gain me experience.
Formal education will indeed help you to make a living (though many MBA's are struggling to get jobs and pay off debt) but what you learn by yourself may be the pathway to a fortune. Following conventional wisdom will not equip you to handle and think about the next unique, groundbreaking advance.