You need to be a "thinker" and also to know - what you don't know.  It's at that time, you need to know WHERE to get the advice from reliable sources.  You also need to be able to think laterally. how to change direction quickly.  Does that mean you need to be intelligent?  Perhaps so.  It doesn't mean you need a Masters Degree.

I would think a little smarts goes a long way.  What do you think? @Liam Shorte @Jef Lippiatt @Jacqui Pryor @Wendy Huang @Denise Hall @Prosper Taruvinga @Chelsea Creamer @Sandra Wright 

Agree with @Rosemary Parker-Hatfield . You don't need to be "educated". You do need to be able to think laterally and adapt quickly. 

Intelligence only takes you so far though. It's persistence and determination that rules in business.